introduction to a literature review

How to write a literature review introduction (+ examples)

The introduction to a literature review serves as your reader’s guide through your academic work and thought process. Explore the significance of literature review introductions in review papers, academic papers, essays, theses, and dissertations. We delve into the purpose and necessity of these introductions, explore the essential components of literature review introductions, and provide step-by-step guidance on how to craft your own, along with examples.

Why you need an introduction for a literature review

When you need an introduction for a literature review, what to include in a literature review introduction, examples of literature review introductions, steps to write your own literature review introduction.

A literature review is a comprehensive examination of the international academic literature concerning a particular topic. It involves summarizing published works, theories, and concepts while also highlighting gaps and offering critical reflections.

In academic writing , the introduction for a literature review is an indispensable component. Effective academic writing requires proper paragraph structuring to guide your reader through your argumentation. This includes providing an introduction to your literature review.

It is imperative to remember that you should never start sharing your findings abruptly. Even if there isn’t a dedicated introduction section .

Instead, you should always offer some form of introduction to orient the reader and clarify what they can expect.

There are three main scenarios in which you need an introduction for a literature review:

• Academic literature review papers: When your literature review constitutes the entirety of an academic review paper, a more substantial introduction is necessary. This introduction should resemble the standard introduction found in regular academic papers.
• Literature review section in an academic paper or essay: While this section tends to be brief, it’s important to precede the detailed literature review with a few introductory sentences. This helps orient the reader before delving into the literature itself.
• Literature review chapter or section in your thesis/dissertation: Every thesis and dissertation includes a literature review component, which also requires a concise introduction to set the stage for the subsequent review.

You may also like: How to write a fantastic thesis introduction (+15 examples)

It is crucial to customize the content and depth of your literature review introduction according to the specific format of your academic work.

In practical terms, this implies, for instance, that the introduction in an academic literature review paper, especially one derived from a systematic literature review , is quite comprehensive. Particularly compared to the rather brief one or two introductory sentences that are often found at the beginning of a literature review section in a standard academic paper. The introduction to the literature review chapter in a thesis or dissertation again adheres to different standards.

Here’s a structured breakdown based on length and the necessary information:

Academic literature review paper

The introduction of an academic literature review paper, which does not rely on empirical data, often necessitates a more extensive introduction than the brief literature review introductions typically found in empirical papers. It should encompass:

• The research problem: Clearly articulate the problem or question that your literature review aims to address.
• The research gap: Highlight the existing gaps, limitations, or unresolved aspects within the current body of literature related to the research problem.
• The research relevance: Explain why the chosen research problem and its subsequent investigation through a literature review are significant and relevant in your academic field.
• The literature review method: If applicable, describe the methodology employed in your literature review, especially if it is a systematic review or follows a specific research framework.
• The main findings or insights of the literature review: Summarize the key discoveries, insights, or trends that have emerged from your comprehensive review of the literature.
• The main argument of the literature review: Conclude the introduction by outlining the primary argument or statement that your literature review will substantiate, linking it to the research problem and relevance you’ve established.
• Preview of the literature review’s structure: Offer a glimpse into the organization of the literature review paper, acting as a guide for the reader. This overview outlines the subsequent sections of the paper and provides an understanding of what to anticipate.

By addressing these elements, your introduction will provide a clear and structured overview of what readers can expect in your literature review paper.

Regular literature review section in an academic article or essay

Most academic articles or essays incorporate regular literature review sections, often placed after the introduction. These sections serve to establish a scholarly basis for the research or discussion within the paper.

In a standard 8000-word journal article, the literature review section typically spans between 750 and 1250 words. The first few sentences or the first paragraph within this section often serve as an introduction. It should encompass:

• An introduction to the topic: When delving into the academic literature on a specific topic, it’s important to provide a smooth transition that aids the reader in comprehending why certain aspects will be discussed within your literature review.
• The core argument: While literature review sections primarily synthesize the work of other scholars, they should consistently connect to your central argument. This central argument serves as the crux of your message or the key takeaway you want your readers to retain. By positioning it at the outset of the literature review section and systematically substantiating it with evidence, you not only enhance reader comprehension but also elevate overall readability. This primary argument can typically be distilled into 1-2 succinct sentences.

In some cases, you might include:

• Methodology: Details about the methodology used, but only if your literature review employed a specialized method. If your approach involved a broader overview without a systematic methodology, you can omit this section, thereby conserving word count.

By addressing these elements, your introduction will effectively integrate your literature review into the broader context of your academic paper or essay. This will, in turn, assist your reader in seamlessly following your overarching line of argumentation.

Introduction to a literature review chapter in thesis or dissertation

The literature review typically constitutes a distinct chapter within a thesis or dissertation. Often, it is Chapter 2 of a thesis or dissertation.

Some students choose to incorporate a brief introductory section at the beginning of each chapter, including the literature review chapter. Alternatively, others opt to seamlessly integrate the introduction into the initial sentences of the literature review itself. Both approaches are acceptable, provided that you incorporate the following elements:

• Purpose of the literature review and its relevance to the thesis/dissertation research: Explain the broader objectives of the literature review within the context of your research and how it contributes to your thesis or dissertation. Essentially, you’re telling the reader why this literature review is important and how it fits into the larger scope of your academic work.
• Primary argument: Succinctly communicate what you aim to prove, explain, or explore through the review of existing literature. This statement helps guide the reader’s understanding of the review’s purpose and what to expect from it.
• Preview of the literature review’s content: Provide a brief overview of the topics or themes that your literature review will cover. It’s like a roadmap for the reader, outlining the main areas of focus within the review. This preview can help the reader anticipate the structure and organization of your literature review.
• Methodology: If your literature review involved a specific research method, such as a systematic review or meta-analysis, you should briefly describe that methodology. However, this is not always necessary, especially if your literature review is more of a narrative synthesis without a distinct research method.

By addressing these elements, your introduction will empower your literature review to play a pivotal role in your thesis or dissertation research. It will accomplish this by integrating your research into the broader academic literature and providing a solid theoretical foundation for your work.

Comprehending the art of crafting your own literature review introduction becomes significantly more accessible when you have concrete examples to examine. Here, you will find several examples that meet, or in most cases, adhere to the criteria described earlier.

Example 1: An effective introduction for an academic literature review paper

To begin, let’s delve into the introduction of an academic literature review paper. We will examine the paper “How does culture influence innovation? A systematic literature review”, which was published in 2018 in the journal Management Decision.

The entire introduction spans 611 words and is divided into five paragraphs. In this introduction, the authors accomplish the following:

• In the first paragraph, the authors introduce the broader topic of the literature review, which focuses on innovation and its significance in the context of economic competition. They underscore the importance of this topic, highlighting its relevance for both researchers and policymakers.
• In the second paragraph, the authors narrow down their focus to emphasize the specific role of culture in relation to innovation.
• In the third paragraph, the authors identify research gaps, noting that existing studies are often fragmented and disconnected. They then emphasize the value of conducting a systematic literature review to enhance our understanding of the topic.
• In the fourth paragraph, the authors introduce their specific objectives and explain how their insights can benefit other researchers and business practitioners.
• In the fifth and final paragraph, the authors provide an overview of the paper’s organization and structure.

In summary, this introduction stands as a solid example. While the authors deviate from previewing their key findings (which is a common practice at least in the social sciences), they do effectively cover all the other previously mentioned points.

Example 2: An effective introduction to a literature review section in an academic paper

The second example represents a typical academic paper, encompassing not only a literature review section but also empirical data, a case study, and other elements. We will closely examine the introduction to the literature review section in the paper “The environmentalism of the subalterns: a case study of environmental activism in Eastern Kurdistan/Rojhelat”, which was published in 2021 in the journal Local Environment.

The paper begins with a general introduction and then proceeds to the literature review, designated by the authors as their conceptual framework. Of particular interest is the first paragraph of this conceptual framework, comprising 142 words across five sentences:

“ A peripheral and marginalised nationality within a multinational though-Persian dominated Iranian society, the Kurdish people of Iranian Kurdistan (a region referred by the Kurds as Rojhelat/Eastern Kurdi-stan) have since the early twentieth century been subject to multifaceted and systematic discriminatory and exclusionary state policy in Iran. This condition has left a population of 12–15 million Kurds in Iran suffering from structural inequalities, disenfranchisement and deprivation. Mismanagement of Kurdistan’s natural resources and the degradation of its natural environmental are among examples of this disenfranchisement. As asserted by Julian Agyeman (2005), structural inequalities that sustain the domination of political and economic elites often simultaneously result in environmental degradation, injustice and discrimination against subaltern communities. This study argues that the environmental struggle in Eastern Kurdistan can be asserted as a (sub)element of the Kurdish liberation movement in Iran. Conceptually this research is inspired by and has been conducted through the lens of ‘subalternity’ ” ( Hassaniyan, 2021, p. 931 ).

In this first paragraph, the author is doing the following:

• The author contextualises the research
• The author links the research focus to the international literature on structural inequalities
• The author clearly presents the argument of the research
• The author clarifies how the research is inspired by and uses the concept of ‘subalternity’.

Thus, the author successfully introduces the literature review, from which point onward it dives into the main concept (‘subalternity’) of the research, and reviews the literature on socio-economic justice and environmental degradation.

While introductions to a literature review section aren’t always required to offer the same level of study context detail as demonstrated here, this introduction serves as a commendable model for orienting the reader within the literature review. It effectively underscores the literature review’s significance within the context of the study being conducted.

Examples 3-5: Effective introductions to literature review chapters

The introduction to a literature review chapter can vary in length, depending largely on the overall length of the literature review chapter itself. For example, a master’s thesis typically features a more concise literature review, thus necessitating a shorter introduction. In contrast, a Ph.D. thesis, with its more extensive literature review, often includes a more detailed introduction.

Numerous universities offer online repositories where you can access theses and dissertations from previous years, serving as valuable sources of reference. Many of these repositories, however, may require you to log in through your university account. Nevertheless, a few open-access repositories are accessible to anyone, such as the one by the University of Manchester . It’s important to note though that copyright restrictions apply to these resources, just as they would with published papers.

Master’s thesis literature review introduction

The first example is “Benchmarking Asymmetrical Heating Models of Spider Pulsar Companions” by P. Sun, a master’s thesis completed at the University of Manchester on January 9, 2024. The author, P. Sun, introduces the literature review chapter very briefly but effectively:

PhD thesis literature review chapter introduction

The second example is Deep Learning on Semi-Structured Data and its Applications to Video-Game AI, Woof, W. (Author). 31 Dec 2020, a PhD thesis completed at the University of Manchester . In Chapter 2, the author offers a comprehensive introduction to the topic in four paragraphs, with the final paragraph serving as an overview of the chapter’s structure:

PhD thesis literature review introduction

The last example is the doctoral thesis Metacognitive strategies and beliefs: Child correlates and early experiences Chan, K. Y. M. (Author). 31 Dec 2020 . The author clearly conducted a systematic literature review, commencing the review section with a discussion of the methodology and approach employed in locating and analyzing the selected records.

Having absorbed all of this information, let’s recap the essential steps and offer a succinct guide on how to proceed with creating your literature review introduction:

• Contextualize your review : Begin by clearly identifying the academic context in which your literature review resides and determining the necessary information to include.
• Outline your structure : Develop a structured outline for your literature review, highlighting the essential information you plan to incorporate in your introduction.
• Literature review process : Conduct a rigorous literature review, reviewing and analyzing relevant sources.
• Summarize and abstract : After completing the review, synthesize the findings and abstract key insights, trends, and knowledge gaps from the literature.
• Craft the introduction : Write your literature review introduction with meticulous attention to the seamless integration of your review into the larger context of your work. Ensure that your introduction effectively elucidates your rationale for the chosen review topics and the underlying reasons guiding your selection.

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What is a Literature Review? How to Write It (with Examples)

A literature review is a critical analysis and synthesis of existing research on a particular topic. It provides an overview of the current state of knowledge, identifies gaps, and highlights key findings in the literature. 1 The purpose of a literature review is to situate your own research within the context of existing scholarship, demonstrating your understanding of the topic and showing how your work contributes to the ongoing conversation in the field. Learning how to write a literature review is a critical tool for successful research. Your ability to summarize and synthesize prior research pertaining to a certain topic demonstrates your grasp on the topic of study, and assists in the learning process. 

Table of Contents

• What is the purpose of literature review? 
• a. Habitat Loss and Species Extinction: 
• b. Range Shifts and Phenological Changes: 
• c. Ocean Acidification and Coral Reefs: 
• d. Adaptive Strategies and Conservation Efforts: 
• How to write a good literature review 
• Choose a Topic and Define the Research Question: 
• Decide on the Scope of Your Review: 
• Select Databases for Searches: 
• Conduct Searches and Keep Track: 
• Review the Literature: 
• Organize and Write Your Literature Review: 
• Frequently asked questions 

What is a literature review?

A well-conducted literature review demonstrates the researcher’s familiarity with the existing literature, establishes the context for their own research, and contributes to scholarly conversations on the topic. One of the purposes of a literature review is also to help researchers avoid duplicating previous work and ensure that their research is informed by and builds upon the existing body of knowledge.

What is the purpose of literature review?

A literature review serves several important purposes within academic and research contexts. Here are some key objectives and functions of a literature review: 2  

• Contextualizing the Research Problem: The literature review provides a background and context for the research problem under investigation. It helps to situate the study within the existing body of knowledge. 
• Identifying Gaps in Knowledge: By identifying gaps, contradictions, or areas requiring further research, the researcher can shape the research question and justify the significance of the study. This is crucial for ensuring that the new research contributes something novel to the field. 
• Understanding Theoretical and Conceptual Frameworks: Literature reviews help researchers gain an understanding of the theoretical and conceptual frameworks used in previous studies. This aids in the development of a theoretical framework for the current research. 
• Providing Methodological Insights: Another purpose of literature reviews is that it allows researchers to learn about the methodologies employed in previous studies. This can help in choosing appropriate research methods for the current study and avoiding pitfalls that others may have encountered. 
• Establishing Credibility: A well-conducted literature review demonstrates the researcher’s familiarity with existing scholarship, establishing their credibility and expertise in the field. It also helps in building a solid foundation for the new research. 
• Informing Hypotheses or Research Questions: The literature review guides the formulation of hypotheses or research questions by highlighting relevant findings and areas of uncertainty in existing literature. 

Literature review example

Let’s delve deeper with a literature review example: Let’s say your literature review is about the impact of climate change on biodiversity. You might format your literature review into sections such as the effects of climate change on habitat loss and species extinction, phenological changes, and marine biodiversity. Each section would then summarize and analyze relevant studies in those areas, highlighting key findings and identifying gaps in the research. The review would conclude by emphasizing the need for further research on specific aspects of the relationship between climate change and biodiversity. The following literature review template provides a glimpse into the recommended literature review structure and content, demonstrating how research findings are organized around specific themes within a broader topic. 

Literature Review on Climate Change Impacts on Biodiversity:

Climate change is a global phenomenon with far-reaching consequences, including significant impacts on biodiversity. This literature review synthesizes key findings from various studies: 

a. Habitat Loss and Species Extinction:

Climate change-induced alterations in temperature and precipitation patterns contribute to habitat loss, affecting numerous species (Thomas et al., 2004). The review discusses how these changes increase the risk of extinction, particularly for species with specific habitat requirements. 

b. Range Shifts and Phenological Changes:

Observations of range shifts and changes in the timing of biological events (phenology) are documented in response to changing climatic conditions (Parmesan & Yohe, 2003). These shifts affect ecosystems and may lead to mismatches between species and their resources. 

c. Ocean Acidification and Coral Reefs:

The review explores the impact of climate change on marine biodiversity, emphasizing ocean acidification’s threat to coral reefs (Hoegh-Guldberg et al., 2007). Changes in pH levels negatively affect coral calcification, disrupting the delicate balance of marine ecosystems. 

d. Adaptive Strategies and Conservation Efforts:

Recognizing the urgency of the situation, the literature review discusses various adaptive strategies adopted by species and conservation efforts aimed at mitigating the impacts of climate change on biodiversity (Hannah et al., 2007). It emphasizes the importance of interdisciplinary approaches for effective conservation planning. 

How to write a good literature review

Writing a literature review involves summarizing and synthesizing existing research on a particular topic. A good literature review format should include the following elements. 

Introduction: The introduction sets the stage for your literature review, providing context and introducing the main focus of your review. 

• Opening Statement: Begin with a general statement about the broader topic and its significance in the field. 
• Scope and Purpose: Clearly define the scope of your literature review. Explain the specific research question or objective you aim to address. 
• Organizational Framework: Briefly outline the structure of your literature review, indicating how you will categorize and discuss the existing research. 
• Significance of the Study: Highlight why your literature review is important and how it contributes to the understanding of the chosen topic. 
• Thesis Statement: Conclude the introduction with a concise thesis statement that outlines the main argument or perspective you will develop in the body of the literature review. 

Body: The body of the literature review is where you provide a comprehensive analysis of existing literature, grouping studies based on themes, methodologies, or other relevant criteria. 

• Organize by Theme or Concept: Group studies that share common themes, concepts, or methodologies. Discuss each theme or concept in detail, summarizing key findings and identifying gaps or areas of disagreement. 
• Critical Analysis: Evaluate the strengths and weaknesses of each study. Discuss the methodologies used, the quality of evidence, and the overall contribution of each work to the understanding of the topic. 
• Synthesis of Findings: Synthesize the information from different studies to highlight trends, patterns, or areas of consensus in the literature. 
• Identification of Gaps: Discuss any gaps or limitations in the existing research and explain how your review contributes to filling these gaps. 
• Transition between Sections: Provide smooth transitions between different themes or concepts to maintain the flow of your literature review. 

Conclusion: The conclusion of your literature review should summarize the main findings, highlight the contributions of the review, and suggest avenues for future research. 

• Summary of Key Findings: Recap the main findings from the literature and restate how they contribute to your research question or objective. 
• Contributions to the Field: Discuss the overall contribution of your literature review to the existing knowledge in the field. 
• Implications and Applications: Explore the practical implications of the findings and suggest how they might impact future research or practice. 
• Recommendations for Future Research: Identify areas that require further investigation and propose potential directions for future research in the field. 
• Final Thoughts: Conclude with a final reflection on the importance of your literature review and its relevance to the broader academic community. 

Conducting a literature review

Conducting a literature review is an essential step in research that involves reviewing and analyzing existing literature on a specific topic. It’s important to know how to do a literature review effectively, so here are the steps to follow: 1  

Choose a Topic and Define the Research Question:

• Select a topic that is relevant to your field of study. 
• Clearly define your research question or objective. Determine what specific aspect of the topic do you want to explore? 

Decide on the Scope of Your Review:

• Determine the timeframe for your literature review. Are you focusing on recent developments, or do you want a historical overview? 
• Consider the geographical scope. Is your review global, or are you focusing on a specific region? 
• Define the inclusion and exclusion criteria. What types of sources will you include? Are there specific types of studies or publications you will exclude? 

Select Databases for Searches:

• Identify relevant databases for your field. Examples include PubMed, IEEE Xplore, Scopus, Web of Science, and Google Scholar. 
• Consider searching in library catalogs, institutional repositories, and specialized databases related to your topic. 

Conduct Searches and Keep Track:

• Develop a systematic search strategy using keywords, Boolean operators (AND, OR, NOT), and other search techniques. 
• Record and document your search strategy for transparency and replicability. 
• Keep track of the articles, including publication details, abstracts, and links. Use citation management tools like EndNote, Zotero, or Mendeley to organize your references. 

Review the Literature:

• Evaluate the relevance and quality of each source. Consider the methodology, sample size, and results of studies. 
• Organize the literature by themes or key concepts. Identify patterns, trends, and gaps in the existing research. 
• Summarize key findings and arguments from each source. Compare and contrast different perspectives. 
• Identify areas where there is a consensus in the literature and where there are conflicting opinions. 
• Provide critical analysis and synthesis of the literature. What are the strengths and weaknesses of existing research? 

Organize and Write Your Literature Review:

• Literature review outline should be based on themes, chronological order, or methodological approaches. 
• Write a clear and coherent narrative that synthesizes the information gathered. 
• Use proper citations for each source and ensure consistency in your citation style (APA, MLA, Chicago, etc.). 
• Conclude your literature review by summarizing key findings, identifying gaps, and suggesting areas for future research. 

The literature review sample and detailed advice on writing and conducting a review will help you produce a well-structured report. But remember that a literature review is an ongoing process, and it may be necessary to revisit and update it as your research progresses. 

Frequently asked questions

A literature review is a critical and comprehensive analysis of existing literature (published and unpublished works) on a specific topic or research question and provides a synthesis of the current state of knowledge in a particular field. A well-conducted literature review is crucial for researchers to build upon existing knowledge, avoid duplication of efforts, and contribute to the advancement of their field. It also helps researchers situate their work within a broader context and facilitates the development of a sound theoretical and conceptual framework for their studies.

Literature review is a crucial component of research writing, providing a solid background for a research paper’s investigation. The aim is to keep professionals up to date by providing an understanding of ongoing developments within a specific field, including research methods, and experimental techniques used in that field, and present that knowledge in the form of a written report. Also, the depth and breadth of the literature review emphasizes the credibility of the scholar in his or her field.  

Before writing a literature review, it’s essential to undertake several preparatory steps to ensure that your review is well-researched, organized, and focused. This includes choosing a topic of general interest to you and doing exploratory research on that topic, writing an annotated bibliography, and noting major points, especially those that relate to the position you have taken on the topic. 

Literature reviews and academic research papers are essential components of scholarly work but serve different purposes within the academic realm. 3 A literature review aims to provide a foundation for understanding the current state of research on a particular topic, identify gaps or controversies, and lay the groundwork for future research. Therefore, it draws heavily from existing academic sources, including books, journal articles, and other scholarly publications. In contrast, an academic research paper aims to present new knowledge, contribute to the academic discourse, and advance the understanding of a specific research question. Therefore, it involves a mix of existing literature (in the introduction and literature review sections) and original data or findings obtained through research methods. 

Literature reviews are essential components of academic and research papers, and various strategies can be employed to conduct them effectively. If you want to know how to write a literature review for a research paper, here are four common approaches that are often used by researchers.  Chronological Review: This strategy involves organizing the literature based on the chronological order of publication. It helps to trace the development of a topic over time, showing how ideas, theories, and research have evolved.  Thematic Review: Thematic reviews focus on identifying and analyzing themes or topics that cut across different studies. Instead of organizing the literature chronologically, it is grouped by key themes or concepts, allowing for a comprehensive exploration of various aspects of the topic.  Methodological Review: This strategy involves organizing the literature based on the research methods employed in different studies. It helps to highlight the strengths and weaknesses of various methodologies and allows the reader to evaluate the reliability and validity of the research findings.  Theoretical Review: A theoretical review examines the literature based on the theoretical frameworks used in different studies. This approach helps to identify the key theories that have been applied to the topic and assess their contributions to the understanding of the subject.  It’s important to note that these strategies are not mutually exclusive, and a literature review may combine elements of more than one approach. The choice of strategy depends on the research question, the nature of the literature available, and the goals of the review. Additionally, other strategies, such as integrative reviews or systematic reviews, may be employed depending on the specific requirements of the research.

The literature review format can vary depending on the specific publication guidelines. However, there are some common elements and structures that are often followed. Here is a general guideline for the format of a literature review:  Introduction:   Provide an overview of the topic.  Define the scope and purpose of the literature review.  State the research question or objective.  Body:   Organize the literature by themes, concepts, or chronology.  Critically analyze and evaluate each source.  Discuss the strengths and weaknesses of the studies.  Highlight any methodological limitations or biases.  Identify patterns, connections, or contradictions in the existing research.  Conclusion:   Summarize the key points discussed in the literature review.  Highlight the research gap.  Address the research question or objective stated in the introduction.  Highlight the contributions of the review and suggest directions for future research.

Both annotated bibliographies and literature reviews involve the examination of scholarly sources. While annotated bibliographies focus on individual sources with brief annotations, literature reviews provide a more in-depth, integrated, and comprehensive analysis of existing literature on a specific topic. The key differences are as follows: 

References 

• Denney, A. S., & Tewksbury, R. (2013). How to write a literature review.  Journal of criminal justice education ,  24 (2), 218-234. 
• Pan, M. L. (2016).  Preparing literature reviews: Qualitative and quantitative approaches . Taylor & Francis. 
• Cantero, C. (2019). How to write a literature review.  San José State University Writing Center . 

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• UConn Library
• Literature Review: The What, Why and How-to Guide
• Introduction

Literature Review: The What, Why and How-to Guide — Introduction

• Getting Started
• How to Pick a Topic
• Strategies to Find Sources
• Evaluating Sources & Lit. Reviews
• Tips for Writing Literature Reviews
• Writing Literature Review: Useful Sites
• Citation Resources
• Other Academic Writings

What are Literature Reviews?

So, what is a literature review? "A literature review is an account of what has been published on a topic by accredited scholars and researchers. In writing the literature review, your purpose is to convey to your reader what knowledge and ideas have been established on a topic, and what their strengths and weaknesses are. As a piece of writing, the literature review must be defined by a guiding concept (e.g., your research objective, the problem or issue you are discussing, or your argumentative thesis). It is not just a descriptive list of the material available, or a set of summaries." Taylor, D.  The literature review: A few tips on conducting it . University of Toronto Health Sciences Writing Centre.

Goals of Literature Reviews

What are the goals of creating a Literature Review?  A literature could be written to accomplish different aims:

• To develop a theory or evaluate an existing theory
• To summarize the historical or existing state of a research topic
• Identify a problem in a field of research 

Baumeister, R. F., & Leary, M. R. (1997). Writing narrative literature reviews .  Review of General Psychology , 1 (3), 311-320.

What kinds of sources require a Literature Review?

• A research paper assigned in a course
• A thesis or dissertation
• A grant proposal
• An article intended for publication in a journal

All these instances require you to collect what has been written about your research topic so that you can demonstrate how your own research sheds new light on the topic.

Types of Literature Reviews

What kinds of literature reviews are written?

Narrative review: The purpose of this type of review is to describe the current state of the research on a specific topic/research and to offer a critical analysis of the literature reviewed. Studies are grouped by research/theoretical categories, and themes and trends, strengths and weakness, and gaps are identified. The review ends with a conclusion section which summarizes the findings regarding the state of the research of the specific study, the gaps identify and if applicable, explains how the author's research will address gaps identify in the review and expand the knowledge on the topic reviewed.

• Example : Predictors and Outcomes of U.S. Quality Maternity Leave: A Review and Conceptual Framework:  10.1177/08948453211037398  

Systematic review : "The authors of a systematic review use a specific procedure to search the research literature, select the studies to include in their review, and critically evaluate the studies they find." (p. 139). Nelson, L. K. (2013). Research in Communication Sciences and Disorders . Plural Publishing.

• Example : The effect of leave policies on increasing fertility: a systematic review:  10.1057/s41599-022-01270-w

Meta-analysis : "Meta-analysis is a method of reviewing research findings in a quantitative fashion by transforming the data from individual studies into what is called an effect size and then pooling and analyzing this information. The basic goal in meta-analysis is to explain why different outcomes have occurred in different studies." (p. 197). Roberts, M. C., & Ilardi, S. S. (2003). Handbook of Research Methods in Clinical Psychology . Blackwell Publishing.

• Example : Employment Instability and Fertility in Europe: A Meta-Analysis:  10.1215/00703370-9164737

Meta-synthesis : "Qualitative meta-synthesis is a type of qualitative study that uses as data the findings from other qualitative studies linked by the same or related topic." (p.312). Zimmer, L. (2006). Qualitative meta-synthesis: A question of dialoguing with texts .  Journal of Advanced Nursing , 53 (3), 311-318.

• Example : Women’s perspectives on career successes and barriers: A qualitative meta-synthesis:  10.1177/05390184221113735

Literature Reviews in the Health Sciences

• UConn Health subject guide on systematic reviews Explanation of the different review types used in health sciences literature as well as tools to help you find the right review type
• << Previous: Getting Started
• Next: How to Pick a Topic >>
• Last Updated: Sep 21, 2022 2:16 PM
• URL: https://guides.lib.uconn.edu/literaturereview

Purdue Online Writing Lab Purdue OWL® College of Liberal Arts

Writing a Literature Review

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A literature review is a document or section of a document that collects key sources on a topic and discusses those sources in conversation with each other (also called synthesis ). The lit review is an important genre in many disciplines, not just literature (i.e., the study of works of literature such as novels and plays). When we say “literature review” or refer to “the literature,” we are talking about the research ( scholarship ) in a given field. You will often see the terms “the research,” “the scholarship,” and “the literature” used mostly interchangeably.

Where, when, and why would I write a lit review?

There are a number of different situations where you might write a literature review, each with slightly different expectations; different disciplines, too, have field-specific expectations for what a literature review is and does. For instance, in the humanities, authors might include more overt argumentation and interpretation of source material in their literature reviews, whereas in the sciences, authors are more likely to report study designs and results in their literature reviews; these differences reflect these disciplines’ purposes and conventions in scholarship. You should always look at examples from your own discipline and talk to professors or mentors in your field to be sure you understand your discipline’s conventions, for literature reviews as well as for any other genre.

A literature review can be a part of a research paper or scholarly article, usually falling after the introduction and before the research methods sections. In these cases, the lit review just needs to cover scholarship that is important to the issue you are writing about; sometimes it will also cover key sources that informed your research methodology.

Lit reviews can also be standalone pieces, either as assignments in a class or as publications. In a class, a lit review may be assigned to help students familiarize themselves with a topic and with scholarship in their field, get an idea of the other researchers working on the topic they’re interested in, find gaps in existing research in order to propose new projects, and/or develop a theoretical framework and methodology for later research. As a publication, a lit review usually is meant to help make other scholars’ lives easier by collecting and summarizing, synthesizing, and analyzing existing research on a topic. This can be especially helpful for students or scholars getting into a new research area, or for directing an entire community of scholars toward questions that have not yet been answered.

What are the parts of a lit review?

Most lit reviews use a basic introduction-body-conclusion structure; if your lit review is part of a larger paper, the introduction and conclusion pieces may be just a few sentences while you focus most of your attention on the body. If your lit review is a standalone piece, the introduction and conclusion take up more space and give you a place to discuss your goals, research methods, and conclusions separately from where you discuss the literature itself.

Introduction:

• An introductory paragraph that explains what your working topic and thesis is
• A forecast of key topics or texts that will appear in the review
• Potentially, a description of how you found sources and how you analyzed them for inclusion and discussion in the review (more often found in published, standalone literature reviews than in lit review sections in an article or research paper)
• Summarize and synthesize: Give an overview of the main points of each source and combine them into a coherent whole
• Analyze and interpret: Don’t just paraphrase other researchers – add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
• Critically Evaluate: Mention the strengths and weaknesses of your sources
• Write in well-structured paragraphs: Use transition words and topic sentence to draw connections, comparisons, and contrasts.

Conclusion:

• Summarize the key findings you have taken from the literature and emphasize their significance
• Connect it back to your primary research question

How should I organize my lit review?

Lit reviews can take many different organizational patterns depending on what you are trying to accomplish with the review. Here are some examples:

• Chronological : The simplest approach is to trace the development of the topic over time, which helps familiarize the audience with the topic (for instance if you are introducing something that is not commonly known in your field). If you choose this strategy, be careful to avoid simply listing and summarizing sources in order. Try to analyze the patterns, turning points, and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred (as mentioned previously, this may not be appropriate in your discipline — check with a teacher or mentor if you’re unsure).
• Thematic : If you have found some recurring central themes that you will continue working with throughout your piece, you can organize your literature review into subsections that address different aspects of the topic. For example, if you are reviewing literature about women and religion, key themes can include the role of women in churches and the religious attitude towards women.
• Qualitative versus quantitative research
• Empirical versus theoretical scholarship
• Divide the research by sociological, historical, or cultural sources
• Theoretical : In many humanities articles, the literature review is the foundation for the theoretical framework. You can use it to discuss various theories, models, and definitions of key concepts. You can argue for the relevance of a specific theoretical approach or combine various theorical concepts to create a framework for your research.

What are some strategies or tips I can use while writing my lit review?

Any lit review is only as good as the research it discusses; make sure your sources are well-chosen and your research is thorough. Don’t be afraid to do more research if you discover a new thread as you’re writing. More info on the research process is available in our "Conducting Research" resources .

As you’re doing your research, create an annotated bibliography ( see our page on the this type of document ). Much of the information used in an annotated bibliography can be used also in a literature review, so you’ll be not only partially drafting your lit review as you research, but also developing your sense of the larger conversation going on among scholars, professionals, and any other stakeholders in your topic.

Usually you will need to synthesize research rather than just summarizing it. This means drawing connections between sources to create a picture of the scholarly conversation on a topic over time. Many student writers struggle to synthesize because they feel they don’t have anything to add to the scholars they are citing; here are some strategies to help you:

• It often helps to remember that the point of these kinds of syntheses is to show your readers how you understand your research, to help them read the rest of your paper.
• Writing teachers often say synthesis is like hosting a dinner party: imagine all your sources are together in a room, discussing your topic. What are they saying to each other?
• Look at the in-text citations in each paragraph. Are you citing just one source for each paragraph? This usually indicates summary only. When you have multiple sources cited in a paragraph, you are more likely to be synthesizing them (not always, but often
• Read more about synthesis here.

The most interesting literature reviews are often written as arguments (again, as mentioned at the beginning of the page, this is discipline-specific and doesn’t work for all situations). Often, the literature review is where you can establish your research as filling a particular gap or as relevant in a particular way. You have some chance to do this in your introduction in an article, but the literature review section gives a more extended opportunity to establish the conversation in the way you would like your readers to see it. You can choose the intellectual lineage you would like to be part of and whose definitions matter most to your thinking (mostly humanities-specific, but this goes for sciences as well). In addressing these points, you argue for your place in the conversation, which tends to make the lit review more compelling than a simple reporting of other sources.

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• What is a Literature Review? | Guide, Template, & Examples

What is a Literature Review? | Guide, Template, & Examples

Published on 22 February 2022 by Shona McCombes . Revised on 7 June 2022.

What is a literature review? A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research.

There are five key steps to writing a literature review:

• Search for relevant literature
• Evaluate sources
• Identify themes, debates and gaps
• Outline the structure
• Write your literature review

A good literature review doesn’t just summarise sources – it analyses, synthesises, and critically evaluates to give a clear picture of the state of knowledge on the subject.

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Table of contents

Why write a literature review, examples of literature reviews, step 1: search for relevant literature, step 2: evaluate and select sources, step 3: identify themes, debates and gaps, step 4: outline your literature review’s structure, step 5: write your literature review, frequently asked questions about literature reviews, introduction.

• Quick Run-through
• Step 1 & 2

When you write a dissertation or thesis, you will have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

• Demonstrate your familiarity with the topic and scholarly context
• Develop a theoretical framework and methodology for your research
• Position yourself in relation to other researchers and theorists
• Show how your dissertation addresses a gap or contributes to a debate

You might also have to write a literature review as a stand-alone assignment. In this case, the purpose is to evaluate the current state of research and demonstrate your knowledge of scholarly debates around a topic.

The content will look slightly different in each case, but the process of conducting a literature review follows the same steps. We’ve written a step-by-step guide that you can follow below.

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Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

• Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
• Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
• Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
• Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research objectives and questions .

If you are writing a literature review as a stand-alone assignment, you will have to choose a focus and develop a central question to direct your search. Unlike a dissertation research question, this question has to be answerable without collecting original data. You should be able to answer it based only on a review of existing publications.

Make a list of keywords

Start by creating a list of keywords related to your research topic. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list if you discover new keywords in the process of your literature search.

• Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
• Body image, self-perception, self-esteem, mental health
• Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some databases to search for journals and articles include:

• Your university’s library catalogue
• Google Scholar
• Project Muse (humanities and social sciences)
• Medline (life sciences and biomedicine)
• EconLit (economics)
• Inspec (physics, engineering and computer science)

You can use boolean operators to help narrow down your search:

Read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

To identify the most important publications on your topic, take note of recurring citations. If the same authors, books or articles keep appearing in your reading, make sure to seek them out.

You probably won’t be able to read absolutely everything that has been written on the topic – you’ll have to evaluate which sources are most relevant to your questions.

For each publication, ask yourself:

• What question or problem is the author addressing?
• What are the key concepts and how are they defined?
• What are the key theories, models and methods? Does the research use established frameworks or take an innovative approach?
• What are the results and conclusions of the study?
• How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
• How does the publication contribute to your understanding of the topic? What are its key insights and arguments?
• What are the strengths and weaknesses of the research?

Make sure the sources you use are credible, and make sure you read any landmark studies and major theories in your field of research.

You can find out how many times an article has been cited on Google Scholar – a high citation count means the article has been influential in the field, and should certainly be included in your literature review.

The scope of your review will depend on your topic and discipline: in the sciences you usually only review recent literature, but in the humanities you might take a long historical perspective (for example, to trace how a concept has changed in meaning over time).

Remember that you can use our template to summarise and evaluate sources you’re thinking about using!

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It’s important to keep track of your sources with references to avoid plagiarism . It can be helpful to make an annotated bibliography, where you compile full reference information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

You can use our free APA Reference Generator for quick, correct, consistent citations.

Prevent plagiarism, run a free check.

To begin organising your literature review’s argument and structure, you need to understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

• Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
• Themes: what questions or concepts recur across the literature?
• Debates, conflicts and contradictions: where do sources disagree?
• Pivotal publications: are there any influential theories or studies that changed the direction of the field?
• Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

• Most research has focused on young women.
• There is an increasing interest in the visual aspects of social media.
• But there is still a lack of robust research on highly-visual platforms like Instagram and Snapchat – this is a gap that you could address in your own research.

There are various approaches to organising the body of a literature review. You should have a rough idea of your strategy before you start writing.

Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarising sources in order.

Try to analyse patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organise your literature review into subsections that address different aspects of the topic.

For example, if you are reviewing literature about inequalities in migrant health outcomes, key themes might include healthcare policy, language barriers, cultural attitudes, legal status, and economic access.

Methodological

If you draw your sources from different disciplines or fields that use a variety of research methods , you might want to compare the results and conclusions that emerge from different approaches. For example:

• Look at what results have emerged in qualitative versus quantitative research
• Discuss how the topic has been approached by empirical versus theoretical scholarship
• Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text, your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

If you are writing the literature review as part of your dissertation or thesis, reiterate your central problem or research question and give a brief summary of the scholarly context. You can emphasise the timeliness of the topic (“many recent studies have focused on the problem of x”) or highlight a gap in the literature (“while there has been much research on x, few researchers have taken y into consideration”).

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, make sure to follow these tips:

• Summarise and synthesise: give an overview of the main points of each source and combine them into a coherent whole.
• Analyse and interpret: don’t just paraphrase other researchers – add your own interpretations, discussing the significance of findings in relation to the literature as a whole.
• Critically evaluate: mention the strengths and weaknesses of your sources.
• Write in well-structured paragraphs: use transitions and topic sentences to draw connections, comparisons and contrasts.

In the conclusion, you should summarise the key findings you have taken from the literature and emphasise their significance.

If the literature review is part of your dissertation or thesis, reiterate how your research addresses gaps and contributes new knowledge, or discuss how you have drawn on existing theories and methods to build a framework for your research. This can lead directly into your methodology section.

A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a dissertation , thesis, research paper , or proposal .

There are several reasons to conduct a literature review at the beginning of a research project:

• To familiarise yourself with the current state of knowledge on your topic
• To ensure that you’re not just repeating what others have already done
• To identify gaps in knowledge and unresolved problems that your research can address
• To develop your theoretical framework and methodology
• To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your  dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

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McCombes, S. (2022, June 07). What is a Literature Review? | Guide, Template, & Examples. Scribbr. Retrieved 22 April 2024, from https://www.scribbr.co.uk/thesis-dissertation/literature-review/

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How To Write A Literature Review - A Complete Guide

Table of Contents

A literature review is much more than just another section in your research paper. It forms the very foundation of your research. It is a formal piece of writing where you analyze the existing theoretical framework, principles, and assumptions and use that as a base to shape your approach to the research question.

Curating and drafting a solid literature review section not only lends more credibility to your research paper but also makes your research tighter and better focused. But, writing literature reviews is a difficult task. It requires extensive reading, plus you have to consider market trends and technological and political changes, which tend to change in the blink of an eye.

Now streamline your literature review process with the help of SciSpace Copilot. With this AI research assistant, you can efficiently synthesize and analyze a vast amount of information, identify key themes and trends, and uncover gaps in the existing research. Get real-time explanations, summaries, and answers to your questions for the paper you're reviewing, making navigating and understanding the complex literature landscape easier.

In this comprehensive guide, we will explore everything from the definition of a literature review, its appropriate length, various types of literature reviews, and how to write one.

What is a literature review?

A literature review is a collation of survey, research, critical evaluation, and assessment of the existing literature in a preferred domain.

Eminent researcher and academic Arlene Fink, in her book Conducting Research Literature Reviews , defines it as the following:

“A literature review surveys books, scholarly articles, and any other sources relevant to a particular issue, area of research, or theory, and by so doing, provides a description, summary, and critical evaluation of these works in relation to the research problem being investigated.

Literature reviews are designed to provide an overview of sources you have explored while researching a particular topic, and to demonstrate to your readers how your research fits within a larger field of study.”

Simply put, a literature review can be defined as a critical discussion of relevant pre-existing research around your research question and carving out a definitive place for your study in the existing body of knowledge. Literature reviews can be presented in multiple ways: a section of an article, the whole research paper itself, or a chapter of your thesis.

A literature review does function as a summary of sources, but it also allows you to analyze further, interpret, and examine the stated theories, methods, viewpoints, and, of course, the gaps in the existing content.

As an author, you can discuss and interpret the research question and its various aspects and debate your adopted methods to support the claim.

What is the purpose of a literature review?

A literature review is meant to help your readers understand the relevance of your research question and where it fits within the existing body of knowledge. As a researcher, you should use it to set the context, build your argument, and establish the need for your study.

What is the importance of a literature review?

The literature review is a critical part of research papers because it helps you:

• Gain an in-depth understanding of your research question and the surrounding area
• Convey that you have a thorough understanding of your research area and are up-to-date with the latest changes and advancements
• Establish how your research is connected or builds on the existing body of knowledge and how it could contribute to further research
• Elaborate on the validity and suitability of your theoretical framework and research methodology
• Identify and highlight gaps and shortcomings in the existing body of knowledge and how things need to change
• Convey to readers how your study is different or how it contributes to the research area

How long should a literature review be?

Ideally, the literature review should take up 15%-40% of the total length of your manuscript. So, if you have a 10,000-word research paper, the minimum word count could be 1500.

Your literature review format depends heavily on the kind of manuscript you are writing — an entire chapter in case of doctoral theses, a part of the introductory section in a research article, to a full-fledged review article that examines the previously published research on a topic.

Another determining factor is the type of research you are doing. The literature review section tends to be longer for secondary research projects than primary research projects.

What are the different types of literature reviews?

All literature reviews are not the same. There are a variety of possible approaches that you can take. It all depends on the type of research you are pursuing.

Here are the different types of literature reviews:

Argumentative review

It is called an argumentative review when you carefully present literature that only supports or counters a specific argument or premise to establish a viewpoint.

Integrative review

It is a type of literature review focused on building a comprehensive understanding of a topic by combining available theoretical frameworks and empirical evidence.

Methodological review

This approach delves into the ''how'' and the ''what" of the research question —  you cannot look at the outcome in isolation; you should also review the methodology used.

Systematic review

This form consists of an overview of existing evidence pertinent to a clearly formulated research question, which uses pre-specified and standardized methods to identify and critically appraise relevant research and collect, report, and analyze data from the studies included in the review.

Meta-analysis review

Meta-analysis uses statistical methods to summarize the results of independent studies. By combining information from all relevant studies, meta-analysis can provide more precise estimates of the effects than those derived from the individual studies included within a review.

Historical review

Historical literature reviews focus on examining research throughout a period, often starting with the first time an issue, concept, theory, or phenomenon emerged in the literature, then tracing its evolution within the scholarship of a discipline. The purpose is to place research in a historical context to show familiarity with state-of-the-art developments and identify future research's likely directions.

Theoretical Review

This form aims to examine the corpus of theory accumulated regarding an issue, concept, theory, and phenomenon. The theoretical literature review helps to establish what theories exist, the relationships between them, the degree the existing approaches have been investigated, and to develop new hypotheses to be tested.

Scoping Review

The Scoping Review is often used at the beginning of an article, dissertation, or research proposal. It is conducted before the research to highlight gaps in the existing body of knowledge and explains why the project should be greenlit.

State-of-the-Art Review

The State-of-the-Art review is conducted periodically, focusing on the most recent research. It describes what is currently known, understood, or agreed upon regarding the research topic and highlights where there are still disagreements.

Can you use the first person in a literature review?

When writing literature reviews, you should avoid the usage of first-person pronouns. It means that instead of "I argue that" or "we argue that," the appropriate expression would be "this research paper argues that."

Do you need an abstract for a literature review?

Ideally, yes. It is always good to have a condensed summary that is self-contained and independent of the rest of your review. As for how to draft one, you can follow the same fundamental idea when preparing an abstract for a literature review. It should also include:

• The research topic and your motivation behind selecting it
• A one-sentence thesis statement
• An explanation of the kinds of literature featured in the review
• Summary of what you've learned
• Conclusions you drew from the literature you reviewed
• Potential implications and future scope for research

Here's an example of the abstract of a literature review

Is a literature review written in the past tense?

Yes, the literature review should ideally be written in the past tense. You should not use the present or future tense when writing one. The exceptions are when you have statements describing events that happened earlier than the literature you are reviewing or events that are currently occurring; then, you can use the past perfect or present perfect tenses.

How many sources for a literature review?

There are multiple approaches to deciding how many sources to include in a literature review section. The first approach would be to look level you are at as a researcher. For instance, a doctoral thesis might need 60+ sources. In contrast, you might only need to refer to 5-15 sources at the undergraduate level.

The second approach is based on the kind of literature review you are doing — whether it is merely a chapter of your paper or if it is a self-contained paper in itself. When it is just a chapter, sources should equal the total number of pages in your article's body. In the second scenario, you need at least three times as many sources as there are pages in your work.

Quick tips on how to write a literature review

To know how to write a literature review, you must clearly understand its impact and role in establishing your work as substantive research material.

You need to follow the below-mentioned steps, to write a literature review:

• Outline the purpose behind the literature review
• Search relevant literature
• Examine and assess the relevant resources
• Discover connections by drawing deep insights from the resources
• Structure planning to write a good literature review

1. Outline and identify the purpose of  a literature review

As a first step on how to write a literature review, you must know what the research question or topic is and what shape you want your literature review to take. Ensure you understand the research topic inside out, or else seek clarifications. You must be able to the answer below questions before you start:

• How many sources do I need to include?
• What kind of sources should I analyze?
• How much should I critically evaluate each source?
• Should I summarize, synthesize or offer a critique of the sources?
• Do I need to include any background information or definitions?

Additionally, you should know that the narrower your research topic is, the swifter it will be for you to restrict the number of sources to be analyzed.

2. Search relevant literature

Dig deeper into search engines to discover what has already been published around your chosen topic. Make sure you thoroughly go through appropriate reference sources like books, reports, journal articles, government docs, and web-based resources.

You must prepare a list of keywords and their different variations. You can start your search from any library’s catalog, provided you are an active member of that institution. The exact keywords can be extended to widen your research over other databases and academic search engines like:

• Google Scholar
• Microsoft Academic
• Science.gov

Besides, it is not advisable to go through every resource word by word. Alternatively, what you can do is you can start by reading the abstract and then decide whether that source is relevant to your research or not.

Additionally, you must spend surplus time assessing the quality and relevance of resources. It would help if you tried preparing a list of citations to ensure that there lies no repetition of authors, publications, or articles in the literature review.

3. Examine and assess the sources

It is nearly impossible for you to go through every detail in the research article. So rather than trying to fetch every detail, you have to analyze and decide which research sources resemble closest and appear relevant to your chosen domain.

While analyzing the sources, you should look to find out answers to questions like:

• What question or problem has the author been describing and debating?
• What is the definition of critical aspects?
• How well the theories, approach, and methodology have been explained?
• Whether the research theory used some conventional or new innovative approach?
• How relevant are the key findings of the work?
• In what ways does it relate to other sources on the same topic?
• What challenges does this research paper pose to the existing theory
• What are the possible contributions or benefits it adds to the subject domain?

Be always mindful that you refer only to credible and authentic resources. It would be best if you always take references from different publications to validate your theory.

Always keep track of important information or data you can present in your literature review right from the beginning. It will help steer your path from any threats of plagiarism and also make it easier to curate an annotated bibliography or reference section.

4. Discover connections

At this stage, you must start deciding on the argument and structure of your literature review. To accomplish this, you must discover and identify the relations and connections between various resources while drafting your abstract.

A few aspects that you should be aware of while writing a literature review include:

• Rise to prominence: Theories and methods that have gained reputation and supporters over time.
• Constant scrutiny: Concepts or theories that repeatedly went under examination.
• Contradictions and conflicts: Theories, both the supporting and the contradictory ones, for the research topic.
• Knowledge gaps: What exactly does it fail to address, and how to bridge them with further research?
• Influential resources: Significant research projects available that have been upheld as milestones or perhaps, something that can modify the current trends

Once you join the dots between various past research works, it will be easier for you to draw a conclusion and identify your contribution to the existing knowledge base.

5. Structure planning to write a good literature review

There exist different ways towards planning and executing the structure of a literature review. The format of a literature review varies and depends upon the length of the research.

Like any other research paper, the literature review format must contain three sections: introduction, body, and conclusion. The goals and objectives of the research question determine what goes inside these three sections.

Nevertheless, a good literature review can be structured according to the chronological, thematic, methodological, or theoretical framework approach.

Literature review samples

1. Standalone

2. As a section of a research paper

How SciSpace Discover makes literature review a breeze?

SciSpace Discover is a one-stop solution to do an effective literature search and get barrier-free access to scientific knowledge. It is an excellent repository where you can find millions of only peer-reviewed articles and full-text PDF files. Here’s more on how you can use it:

Find the right information

Find what you want quickly and easily with comprehensive search filters that let you narrow down papers according to PDF availability, year of publishing, document type, and affiliated institution. Moreover, you can sort the results based on the publishing date, citation count, and relevance.

Assess credibility of papers quickly

When doing the literature review, it is critical to establish the quality of your sources. They form the foundation of your research. SciSpace Discover helps you assess the quality of a source by providing an overview of its references, citations, and performance metrics.

Get the complete picture in no time

SciSpace Discover’s personalized suggestion engine helps you stay on course and get the complete picture of the topic from one place. Every time you visit an article page, it provides you links to related papers. Besides that, it helps you understand what’s trending, who are the top authors, and who are the leading publishers on a topic.

Make referring sources super easy

To ensure you don't lose track of your sources, you must start noting down your references when doing the literature review. SciSpace Discover makes this step effortless. Click the 'cite' button on an article page, and you will receive preloaded citation text in multiple styles — all you've to do is copy-paste it into your manuscript.

Final tips on how to write a literature review

A massive chunk of time and effort is required to write a good literature review. But, if you go about it systematically, you'll be able to save a ton of time and build a solid foundation for your research.

We hope this guide has helped you answer several key questions you have about writing literature reviews.

Would you like to explore SciSpace Discover and kick off your literature search right away? You can get started here .

Frequently Asked Questions (FAQs)

1. how to start a literature review.

• What questions do you want to answer?

• What sources do you need to answer these questions?

• What information do these sources contain?

• How can you use this information to answer your questions?

2. What to include in a literature review?

• A brief background of the problem or issue

• What has previously been done to address the problem or issue

• A description of what you will do in your project

• How this study will contribute to research on the subject

3. Why literature review is important?

The literature review is an important part of any research project because it allows the writer to look at previous studies on a topic and determine existing gaps in the literature, as well as what has already been done. It will also help them to choose the most appropriate method for their own study.

4. How to cite a literature review in APA format?

To cite a literature review in APA style, you need to provide the author's name, the title of the article, and the year of publication. For example: Patel, A. B., & Stokes, G. S. (2012). The relationship between personality and intelligence: A meta-analysis of longitudinal research. Personality and Individual Differences, 53(1), 16-21

5. What are the components of a literature review?

• A brief introduction to the topic, including its background and context. The introduction should also include a rationale for why the study is being conducted and what it will accomplish.

• A description of the methodologies used in the study. This can include information about data collection methods, sample size, and statistical analyses.

• A presentation of the findings in an organized format that helps readers follow along with the author's conclusions.

6. What are common errors in writing literature review?

• Not spending enough time to critically evaluate the relevance of resources, observations and conclusions.

• Totally relying on secondary data while ignoring primary data.

• Letting your personal bias seep into your interpretation of existing literature.

• No detailed explanation of the procedure to discover and identify an appropriate literature review.

7. What are the 5 C's of writing literature review?

• Cite - the sources you utilized and referenced in your research.

• Compare - existing arguments, hypotheses, methodologies, and conclusions found in the knowledge base.

• Contrast - the arguments, topics, methodologies, approaches, and disputes that may be found in the literature.

• Critique - the literature and describe the ideas and opinions you find more convincing and why.

• Connect - the various studies you reviewed in your research.

8. How many sources should a literature review have?

When it is just a chapter, sources should equal the total number of pages in your article's body. if it is a self-contained paper in itself, you need at least three times as many sources as there are pages in your work.

9. Can literature review have diagrams?

• To represent an abstract idea or concept

• To explain the steps of a process or procedure

• To help readers understand the relationships between different concepts

10. How old should sources be in a literature review?

Sources for a literature review should be as current as possible or not older than ten years. The only exception to this rule is if you are reviewing a historical topic and need to use older sources.

11. What are the types of literature review?

• Argumentative review

• Integrative review

• Methodological review

• Systematic review

• Meta-analysis review

• Historical review

• Theoretical review

• Scoping review

• State-of-the-Art review

12. Is a literature review mandatory?

Yes. Literature review is a mandatory part of any research project. It is a critical step in the process that allows you to establish the scope of your research, and provide a background for the rest of your work.

But before you go,

• Six Online Tools for Easy Literature Review
• Evaluating literature review: systematic vs. scoping reviews
• Systematic Approaches to a Successful Literature Review
• Writing Integrative Literature Reviews: Guidelines and Examples

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• 04 December 2020
• Correction 09 December 2020

How to write a superb literature review

Andy Tay is a freelance writer based in Singapore.

You can also search for this author in PubMed   Google Scholar

Literature reviews are important resources for scientists. They provide historical context for a field while offering opinions on its future trajectory. Creating them can provide inspiration for one’s own research, as well as some practice in writing. But few scientists are trained in how to write a review — or in what constitutes an excellent one. Even picking the appropriate software to use can be an involved decision (see ‘Tools and techniques’). So Nature asked editors and working scientists with well-cited reviews for their tips.

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doi: https://doi.org/10.1038/d41586-020-03422-x

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Updates & Corrections

Correction 09 December 2020 : An earlier version of the tables in this article included some incorrect details about the programs Zotero, Endnote and Manubot. These have now been corrected.

Hsing, I.-M., Xu, Y. & Zhao, W. Electroanalysis 19 , 755–768 (2007).

Article   Google Scholar  

Ledesma, H. A. et al. Nature Nanotechnol. 14 , 645–657 (2019).

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Brahlek, M., Koirala, N., Bansal, N. & Oh, S. Solid State Commun. 215–216 , 54–62 (2015).

Choi, Y. & Lee, S. Y. Nature Rev. Chem . https://doi.org/10.1038/s41570-020-00221-w (2020).

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Literature Reviews

What this handout is about.

This handout will explain what literature reviews are and offer insights into the form and construction of literature reviews in the humanities, social sciences, and sciences.

Introduction

OK. You’ve got to write a literature review. You dust off a novel and a book of poetry, settle down in your chair, and get ready to issue a “thumbs up” or “thumbs down” as you leaf through the pages. “Literature review” done. Right?

Wrong! The “literature” of a literature review refers to any collection of materials on a topic, not necessarily the great literary texts of the world. “Literature” could be anything from a set of government pamphlets on British colonial methods in Africa to scholarly articles on the treatment of a torn ACL. And a review does not necessarily mean that your reader wants you to give your personal opinion on whether or not you liked these sources.

What is a literature review, then?

A literature review discusses published information in a particular subject area, and sometimes information in a particular subject area within a certain time period.

A literature review can be just a simple summary of the sources, but it usually has an organizational pattern and combines both summary and synthesis. A summary is a recap of the important information of the source, but a synthesis is a re-organization, or a reshuffling, of that information. It might give a new interpretation of old material or combine new with old interpretations. Or it might trace the intellectual progression of the field, including major debates. And depending on the situation, the literature review may evaluate the sources and advise the reader on the most pertinent or relevant.

But how is a literature review different from an academic research paper?

The main focus of an academic research paper is to develop a new argument, and a research paper is likely to contain a literature review as one of its parts. In a research paper, you use the literature as a foundation and as support for a new insight that you contribute. The focus of a literature review, however, is to summarize and synthesize the arguments and ideas of others without adding new contributions.

Why do we write literature reviews?

Literature reviews provide you with a handy guide to a particular topic. If you have limited time to conduct research, literature reviews can give you an overview or act as a stepping stone. For professionals, they are useful reports that keep them up to date with what is current in the field. For scholars, the depth and breadth of the literature review emphasizes the credibility of the writer in his or her field. Literature reviews also provide a solid background for a research paper’s investigation. Comprehensive knowledge of the literature of the field is essential to most research papers.

Who writes these things, anyway?

Literature reviews are written occasionally in the humanities, but mostly in the sciences and social sciences; in experiment and lab reports, they constitute a section of the paper. Sometimes a literature review is written as a paper in itself.

Let’s get to it! What should I do before writing the literature review?

If your assignment is not very specific, seek clarification from your instructor:

• Roughly how many sources should you include?
• What types of sources (books, journal articles, websites)?
• Should you summarize, synthesize, or critique your sources by discussing a common theme or issue?
• Should you evaluate your sources?
• Should you provide subheadings and other background information, such as definitions and/or a history?

Find models

Look for other literature reviews in your area of interest or in the discipline and read them to get a sense of the types of themes you might want to look for in your own research or ways to organize your final review. You can simply put the word “review” in your search engine along with your other topic terms to find articles of this type on the Internet or in an electronic database. The bibliography or reference section of sources you’ve already read are also excellent entry points into your own research.

Narrow your topic

There are hundreds or even thousands of articles and books on most areas of study. The narrower your topic, the easier it will be to limit the number of sources you need to read in order to get a good survey of the material. Your instructor will probably not expect you to read everything that’s out there on the topic, but you’ll make your job easier if you first limit your scope.

Keep in mind that UNC Libraries have research guides and to databases relevant to many fields of study. You can reach out to the subject librarian for a consultation: https://library.unc.edu/support/consultations/ .

And don’t forget to tap into your professor’s (or other professors’) knowledge in the field. Ask your professor questions such as: “If you had to read only one book from the 90’s on topic X, what would it be?” Questions such as this help you to find and determine quickly the most seminal pieces in the field.

Consider whether your sources are current

Some disciplines require that you use information that is as current as possible. In the sciences, for instance, treatments for medical problems are constantly changing according to the latest studies. Information even two years old could be obsolete. However, if you are writing a review in the humanities, history, or social sciences, a survey of the history of the literature may be what is needed, because what is important is how perspectives have changed through the years or within a certain time period. Try sorting through some other current bibliographies or literature reviews in the field to get a sense of what your discipline expects. You can also use this method to consider what is currently of interest to scholars in this field and what is not.

Strategies for writing the literature review

Find a focus.

A literature review, like a term paper, is usually organized around ideas, not the sources themselves as an annotated bibliography would be organized. This means that you will not just simply list your sources and go into detail about each one of them, one at a time. No. As you read widely but selectively in your topic area, consider instead what themes or issues connect your sources together. Do they present one or different solutions? Is there an aspect of the field that is missing? How well do they present the material and do they portray it according to an appropriate theory? Do they reveal a trend in the field? A raging debate? Pick one of these themes to focus the organization of your review.

Convey it to your reader

A literature review may not have a traditional thesis statement (one that makes an argument), but you do need to tell readers what to expect. Try writing a simple statement that lets the reader know what is your main organizing principle. Here are a couple of examples:

The current trend in treatment for congestive heart failure combines surgery and medicine. More and more cultural studies scholars are accepting popular media as a subject worthy of academic consideration.

Consider organization

You’ve got a focus, and you’ve stated it clearly and directly. Now what is the most effective way of presenting the information? What are the most important topics, subtopics, etc., that your review needs to include? And in what order should you present them? Develop an organization for your review at both a global and local level:

First, cover the basic categories

Just like most academic papers, literature reviews also must contain at least three basic elements: an introduction or background information section; the body of the review containing the discussion of sources; and, finally, a conclusion and/or recommendations section to end the paper. The following provides a brief description of the content of each:

• Introduction: Gives a quick idea of the topic of the literature review, such as the central theme or organizational pattern.
• Body: Contains your discussion of sources and is organized either chronologically, thematically, or methodologically (see below for more information on each).
• Conclusions/Recommendations: Discuss what you have drawn from reviewing literature so far. Where might the discussion proceed?

Organizing the body

Once you have the basic categories in place, then you must consider how you will present the sources themselves within the body of your paper. Create an organizational method to focus this section even further.

To help you come up with an overall organizational framework for your review, consider the following scenario:

You’ve decided to focus your literature review on materials dealing with sperm whales. This is because you’ve just finished reading Moby Dick, and you wonder if that whale’s portrayal is really real. You start with some articles about the physiology of sperm whales in biology journals written in the 1980’s. But these articles refer to some British biological studies performed on whales in the early 18th century. So you check those out. Then you look up a book written in 1968 with information on how sperm whales have been portrayed in other forms of art, such as in Alaskan poetry, in French painting, or on whale bone, as the whale hunters in the late 19th century used to do. This makes you wonder about American whaling methods during the time portrayed in Moby Dick, so you find some academic articles published in the last five years on how accurately Herman Melville portrayed the whaling scene in his novel.

Now consider some typical ways of organizing the sources into a review:

• Chronological: If your review follows the chronological method, you could write about the materials above according to when they were published. For instance, first you would talk about the British biological studies of the 18th century, then about Moby Dick, published in 1851, then the book on sperm whales in other art (1968), and finally the biology articles (1980s) and the recent articles on American whaling of the 19th century. But there is relatively no continuity among subjects here. And notice that even though the sources on sperm whales in other art and on American whaling are written recently, they are about other subjects/objects that were created much earlier. Thus, the review loses its chronological focus.
• By publication: Order your sources by publication chronology, then, only if the order demonstrates a more important trend. For instance, you could order a review of literature on biological studies of sperm whales if the progression revealed a change in dissection practices of the researchers who wrote and/or conducted the studies.
• By trend: A better way to organize the above sources chronologically is to examine the sources under another trend, such as the history of whaling. Then your review would have subsections according to eras within this period. For instance, the review might examine whaling from pre-1600-1699, 1700-1799, and 1800-1899. Under this method, you would combine the recent studies on American whaling in the 19th century with Moby Dick itself in the 1800-1899 category, even though the authors wrote a century apart.
• Thematic: Thematic reviews of literature are organized around a topic or issue, rather than the progression of time. However, progression of time may still be an important factor in a thematic review. For instance, the sperm whale review could focus on the development of the harpoon for whale hunting. While the study focuses on one topic, harpoon technology, it will still be organized chronologically. The only difference here between a “chronological” and a “thematic” approach is what is emphasized the most: the development of the harpoon or the harpoon technology.But more authentic thematic reviews tend to break away from chronological order. For instance, a thematic review of material on sperm whales might examine how they are portrayed as “evil” in cultural documents. The subsections might include how they are personified, how their proportions are exaggerated, and their behaviors misunderstood. A review organized in this manner would shift between time periods within each section according to the point made.
• Methodological: A methodological approach differs from the two above in that the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the “methods” of the researcher or writer. For the sperm whale project, one methodological approach would be to look at cultural differences between the portrayal of whales in American, British, and French art work. Or the review might focus on the economic impact of whaling on a community. A methodological scope will influence either the types of documents in the review or the way in which these documents are discussed. Once you’ve decided on the organizational method for the body of the review, the sections you need to include in the paper should be easy to figure out. They should arise out of your organizational strategy. In other words, a chronological review would have subsections for each vital time period. A thematic review would have subtopics based upon factors that relate to the theme or issue.

Sometimes, though, you might need to add additional sections that are necessary for your study, but do not fit in the organizational strategy of the body. What other sections you include in the body is up to you. Put in only what is necessary. Here are a few other sections you might want to consider:

• Current Situation: Information necessary to understand the topic or focus of the literature review.
• History: The chronological progression of the field, the literature, or an idea that is necessary to understand the literature review, if the body of the literature review is not already a chronology.
• Methods and/or Standards: The criteria you used to select the sources in your literature review or the way in which you present your information. For instance, you might explain that your review includes only peer-reviewed articles and journals.

Questions for Further Research: What questions about the field has the review sparked? How will you further your research as a result of the review?

Begin composing

Once you’ve settled on a general pattern of organization, you’re ready to write each section. There are a few guidelines you should follow during the writing stage as well. Here is a sample paragraph from a literature review about sexism and language to illuminate the following discussion:

However, other studies have shown that even gender-neutral antecedents are more likely to produce masculine images than feminine ones (Gastil, 1990). Hamilton (1988) asked students to complete sentences that required them to fill in pronouns that agreed with gender-neutral antecedents such as “writer,” “pedestrian,” and “persons.” The students were asked to describe any image they had when writing the sentence. Hamilton found that people imagined 3.3 men to each woman in the masculine “generic” condition and 1.5 men per woman in the unbiased condition. Thus, while ambient sexism accounted for some of the masculine bias, sexist language amplified the effect. (Source: Erika Falk and Jordan Mills, “Why Sexist Language Affects Persuasion: The Role of Homophily, Intended Audience, and Offense,” Women and Language19:2).

Use evidence

In the example above, the writers refer to several other sources when making their point. A literature review in this sense is just like any other academic research paper. Your interpretation of the available sources must be backed up with evidence to show that what you are saying is valid.

Be selective

Select only the most important points in each source to highlight in the review. The type of information you choose to mention should relate directly to the review’s focus, whether it is thematic, methodological, or chronological.

Use quotes sparingly

Falk and Mills do not use any direct quotes. That is because the survey nature of the literature review does not allow for in-depth discussion or detailed quotes from the text. Some short quotes here and there are okay, though, if you want to emphasize a point, or if what the author said just cannot be rewritten in your own words. Notice that Falk and Mills do quote certain terms that were coined by the author, not common knowledge, or taken directly from the study. But if you find yourself wanting to put in more quotes, check with your instructor.

Summarize and synthesize

Remember to summarize and synthesize your sources within each paragraph as well as throughout the review. The authors here recapitulate important features of Hamilton’s study, but then synthesize it by rephrasing the study’s significance and relating it to their own work.

Keep your own voice

While the literature review presents others’ ideas, your voice (the writer’s) should remain front and center. Notice that Falk and Mills weave references to other sources into their own text, but they still maintain their own voice by starting and ending the paragraph with their own ideas and their own words. The sources support what Falk and Mills are saying.

Use caution when paraphrasing

When paraphrasing a source that is not your own, be sure to represent the author’s information or opinions accurately and in your own words. In the preceding example, Falk and Mills either directly refer in the text to the author of their source, such as Hamilton, or they provide ample notation in the text when the ideas they are mentioning are not their own, for example, Gastil’s. For more information, please see our handout on plagiarism .

Revise, revise, revise

Draft in hand? Now you’re ready to revise. Spending a lot of time revising is a wise idea, because your main objective is to present the material, not the argument. So check over your review again to make sure it follows the assignment and/or your outline. Then, just as you would for most other academic forms of writing, rewrite or rework the language of your review so that you’ve presented your information in the most concise manner possible. Be sure to use terminology familiar to your audience; get rid of unnecessary jargon or slang. Finally, double check that you’ve documented your sources and formatted the review appropriately for your discipline. For tips on the revising and editing process, see our handout on revising drafts .

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

Anson, Chris M., and Robert A. Schwegler. 2010. The Longman Handbook for Writers and Readers , 6th ed. New York: Longman.

Jones, Robert, Patrick Bizzaro, and Cynthia Selfe. 1997. The Harcourt Brace Guide to Writing in the Disciplines . New York: Harcourt Brace.

Lamb, Sandra E. 1998. How to Write It: A Complete Guide to Everything You’ll Ever Write . Berkeley: Ten Speed Press.

Rosen, Leonard J., and Laurence Behrens. 2003. The Allyn & Bacon Handbook , 5th ed. New York: Longman.

Troyka, Lynn Quittman, and Doug Hesse. 2016. Simon and Schuster Handbook for Writers , 11th ed. London: Pearson.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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What is a literature review?

A literature review is an integrated analysis -- not just a summary-- of scholarly writings and other relevant evidence related directly to your research question.  That is, it represents a synthesis of the evidence that provides background information on your topic and shows a association between the evidence and your research question.

A literature review may be a stand alone work or the introduction to a larger research paper, depending on the assignment.  Rely heavily on the guidelines your instructor has given you.

Why is it important?

A literature review is important because it:

• Explains the background of research on a topic.
• Demonstrates why a topic is significant to a subject area.
• Discovers relationships between research studies/ideas.
• Identifies major themes, concepts, and researchers on a topic.
• Identifies critical gaps and points of disagreement.
• Discusses further research questions that logically come out of the previous studies.

APA7 Style resources

APA Style Blog - for those harder to find answers

1. Choose a topic. Define your research question.

Your literature review should be guided by your central research question.  The literature represents background and research developments related to a specific research question, interpreted and analyzed by you in a synthesized way.

• Make sure your research question is not too broad or too narrow.  Is it manageable?
• Begin writing down terms that are related to your question. These will be useful for searches later.
• If you have the opportunity, discuss your topic with your professor and your class mates.

2. Decide on the scope of your review

How many studies do you need to look at? How comprehensive should it be? How many years should it cover? 

• This may depend on your assignment.  How many sources does the assignment require?

3. Select the databases you will use to conduct your searches.

Make a list of the databases you will search. 

Where to find databases:

• use the tabs on this guide
• Find other databases in the Nursing Information Resources web page
• More on the Medical Library web page
• ... and more on the Yale University Library web page

4. Conduct your searches to find the evidence. Keep track of your searches.

• Use the key words in your question, as well as synonyms for those words, as terms in your search. Use the database tutorials for help.
• Save the searches in the databases. This saves time when you want to redo, or modify, the searches. It is also helpful to use as a guide is the searches are not finding any useful results.
• Review the abstracts of research studies carefully. This will save you time.
• Use the bibliographies and references of research studies you find to locate others.
• Check with your professor, or a subject expert in the field, if you are missing any key works in the field.
• Ask your librarian for help at any time.
• Use a citation manager, such as EndNote as the repository for your citations. See the EndNote tutorials for help.

Review the literature

Some questions to help you analyze the research:

• What was the research question of the study you are reviewing? What were the authors trying to discover?
• Was the research funded by a source that could influence the findings?
• What were the research methodologies? Analyze its literature review, the samples and variables used, the results, and the conclusions.
• Does the research seem to be complete? Could it have been conducted more soundly? What further questions does it raise?
• If there are conflicting studies, why do you think that is?
• How are the authors viewed in the field? Has this study been cited? If so, how has it been analyzed?

Tips: 

• Review the abstracts carefully.  
• Keep careful notes so that you may track your thought processes during the research process.
• Create a matrix of the studies for easy analysis, and synthesis, across all of the studies.
• << Previous: Recommended Books
• Last Updated: Jan 4, 2024 10:52 AM
• URL: https://guides.library.yale.edu/YSNDoctoral

How To Structure Your Literature Review

3 options to help structure your chapter.

By: Amy Rommelspacher (PhD) | Reviewer: Dr Eunice Rautenbach | November 2020 (Updated May 2023)

Writing the literature review chapter can seem pretty daunting when you’re piecing together your dissertation or thesis. As  we’ve discussed before , a good literature review needs to achieve a few very important objectives – it should:

• Demonstrate your knowledge of the research topic
• Identify the gaps in the literature and show how your research links to these
• Provide the foundation for your conceptual framework (if you have one)
• Inform your own  methodology and research design

To achieve this, your literature review needs a well-thought-out structure . Get the structure of your literature review chapter wrong and you’ll struggle to achieve these objectives. Don’t worry though – in this post, we’ll look at how to structure your literature review for maximum impact (and marks!).

But wait – is this the right time?

Deciding on the structure of your literature review should come towards the end of the literature review process – after you have collected and digested the literature, but before you start writing the chapter. 

In other words, you need to first develop a rich understanding of the literature before you even attempt to map out a structure. There’s no use trying to develop a structure before you’ve fully wrapped your head around the existing research.

Equally importantly, you need to have a structure in place before you start writing , or your literature review will most likely end up a rambling, disjointed mess. 

Importantly, don’t feel that once you’ve defined a structure you can’t iterate on it. It’s perfectly natural to adjust as you engage in the writing process. As we’ve discussed before , writing is a way of developing your thinking, so it’s quite common for your thinking to change – and therefore, for your chapter structure to change – as you write. 

Need a helping hand?

Like any other chapter in your thesis or dissertation, your literature review needs to have a clear, logical structure. At a minimum, it should have three essential components – an  introduction , a  body   and a  conclusion . 

Let’s take a closer look at each of these.

1: The Introduction Section

Just like any good introduction, the introduction section of your literature review should introduce the purpose and layout (organisation) of the chapter. In other words, your introduction needs to give the reader a taste of what’s to come, and how you’re going to lay that out. Essentially, you should provide the reader with a high-level roadmap of your chapter to give them a taste of the journey that lies ahead.

Here’s an example of the layout visualised in a literature review introduction:

Your introduction should also outline your topic (including any tricky terminology or jargon) and provide an explanation of the scope of your literature review – in other words, what you  will   and  won’t   be covering (the delimitations ). This helps ringfence your review and achieve a clear focus . The clearer and narrower your focus, the deeper you can dive into the topic (which is typically where the magic lies). 

Depending on the nature of your project, you could also present your stance or point of view at this stage. In other words, after grappling with the literature you’ll have an opinion about what the trends and concerns are in the field as well as what’s lacking. The introduction section can then present these ideas so that it is clear to examiners that you’re aware of how your research connects with existing knowledge .

2: The Body Section

The body of your literature review is the centre of your work. This is where you’ll present, analyse, evaluate and synthesise the existing research. In other words, this is where you’re going to earn (or lose) the most marks. Therefore, it’s important to carefully think about how you will organise your discussion to present it in a clear way. 

The body of your literature review should do just as the description of this chapter suggests. It should “review” the literature – in other words, identify, analyse, and synthesise it. So, when thinking about structuring your literature review, you need to think about which structural approach will provide the best “review” for your specific type of research and objectives (we’ll get to this shortly).

There are (broadly speaking)  three options  for organising your literature review.

Option 1: Chronological (according to date)

Organising the literature chronologically is one of the simplest ways to structure your literature review. You start with what was published first and work your way through the literature until you reach the work published most recently. Pretty straightforward.

The benefit of this option is that it makes it easy to discuss the developments and debates in the field as they emerged over time. Organising your literature chronologically also allows you to highlight how specific articles or pieces of work might have changed the course of the field – in other words, which research has had the most impact . Therefore, this approach is very useful when your research is aimed at understanding how the topic has unfolded over time and is often used by scholars in the field of history. That said, this approach can be utilised by anyone that wants to explore change over time .

For example , if a student of politics is investigating how the understanding of democracy has evolved over time, they could use the chronological approach to provide a narrative that demonstrates how this understanding has changed through the ages.

Here are some questions you can ask yourself to help you structure your literature review chronologically.

• What is the earliest literature published relating to this topic?
• How has the field changed over time? Why?
• What are the most recent discoveries/theories?

In some ways, chronology plays a part whichever way you decide to structure your literature review, because you will always, to a certain extent, be analysing how the literature has developed. However, with the chronological approach, the emphasis is very firmly on how the discussion has evolved over time , as opposed to how all the literature links together (which we’ll discuss next ).

Option 2: Thematic (grouped by theme)

The thematic approach to structuring a literature review means organising your literature by theme or category – for example, by independent variables (i.e. factors that have an impact on a specific outcome).

As you’ve been collecting and synthesising literature , you’ll likely have started seeing some themes or patterns emerging. You can then use these themes or patterns as a structure for your body discussion. The thematic approach is the most common approach and is useful for structuring literature reviews in most fields.

For example, if you were researching which factors contributed towards people trusting an organisation, you might find themes such as consumers’ perceptions of an organisation’s competence, benevolence and integrity. Structuring your literature review thematically would mean structuring your literature review’s body section to discuss each of these themes, one section at a time.

Here are some questions to ask yourself when structuring your literature review by themes:

• Are there any patterns that have come to light in the literature?
• What are the central themes and categories used by the researchers?
• Do I have enough evidence of these themes?

PS – you can see an example of a thematically structured literature review in our literature review sample walkthrough video here.

Option 3: Methodological

The methodological option is a way of structuring your literature review by the research methodologies used . In other words, organising your discussion based on the angle from which each piece of research was approached – for example, qualitative , quantitative or mixed  methodologies.

Structuring your literature review by methodology can be useful if you are drawing research from a variety of disciplines and are critiquing different methodologies. The point of this approach is to question  how  existing research has been conducted, as opposed to  what  the conclusions and/or findings the research were.

For example, a sociologist might centre their research around critiquing specific fieldwork practices. Their literature review will then be a summary of the fieldwork methodologies used by different studies.

Here are some questions you can ask yourself when structuring your literature review according to methodology:

• Which methodologies have been utilised in this field?
• Which methodology is the most popular (and why)?
• What are the strengths and weaknesses of the various methodologies?
• How can the existing methodologies inform my own methodology?

3: The Conclusion Section

Once you’ve completed the body section of your literature review using one of the structural approaches we discussed above, you’ll need to “wrap up” your literature review and pull all the pieces together to set the direction for the rest of your dissertation or thesis.

The conclusion is where you’ll present the key findings of your literature review. In this section, you should emphasise the research that is especially important to your research questions and highlight the gaps that exist in the literature. Based on this, you need to make it clear what you will add to the literature – in other words, justify your own research by showing how it will help fill one or more of the gaps you just identified.

Last but not least, if it’s your intention to develop a conceptual framework for your dissertation or thesis, the conclusion section is a good place to present this.

Example: Thematically Structured Review

In the video below, we unpack a literature review chapter so that you can see an example of a thematically structure review in practice.

Let’s Recap

In this article, we’ve  discussed how to structure your literature review for maximum impact. Here’s a quick recap of what  you need to keep in mind when deciding on your literature review structure:

• Just like other chapters, your literature review needs a clear introduction , body and conclusion .
• The introduction section should provide an overview of what you will discuss in your literature review.
• The body section of your literature review can be organised by chronology , theme or methodology . The right structural approach depends on what you’re trying to achieve with your research.
• The conclusion section should draw together the key findings of your literature review and link them to your research questions.

If you’re ready to get started, be sure to download our free literature review template to fast-track your chapter outline.

Psst… there’s more!

This post is an extract from our bestselling short course, Literature Review Bootcamp . If you want to work smart, you don't want to miss this .

You Might Also Like:

27 Comments

Great work. This is exactly what I was looking for and helps a lot together with your previous post on literature review. One last thing is missing: a link to a great literature chapter of an journal article (maybe with comments of the different sections in this review chapter). Do you know any great literature review chapters?

I agree with you Marin… A great piece

I agree with Marin. This would be quite helpful if you annotate a nicely structured literature from previously published research articles.

Awesome article for my research.

I thank you immensely for this wonderful guide

It is indeed thought and supportive work for the futurist researcher and students

Very educative and good time to get guide. Thank you

Great work, very insightful. Thank you.

Thanks for this wonderful presentation. My question is that do I put all the variables into a single conceptual framework or each hypothesis will have it own conceptual framework?

Thank you very much, very helpful

This is very educative and precise . Thank you very much for dropping this kind of write up .

Pheeww, so damn helpful, thank you for this informative piece.

I’m doing a research project topic ; stool analysis for parasitic worm (enteric) worm, how do I structure it, thanks.

comprehensive explanation. Help us by pasting the URL of some good “literature review” for better understanding.

great piece. thanks for the awesome explanation. it is really worth sharing. I have a little question, if anyone can help me out, which of the options in the body of literature can be best fit if you are writing an architectural thesis that deals with design?

I am doing a research on nanofluids how can l structure it?

Beautifully clear.nThank you!

Lucid! Thankyou!

Brilliant work, well understood, many thanks

I like how this was so clear with simple language 😊😊 thank you so much 😊 for these information 😊

Insightful. I was struggling to come up with a sensible literature review but this has been really helpful. Thank you!

You have given thought-provoking information about the review of the literature.

Thank you. It has made my own research better and to impart your work to students I teach

I learnt a lot from this teaching. It’s a great piece.

I am doing research on EFL teacher motivation for his/her job. How Can I structure it? Is there any detailed template, additional to this?

You are so cool! I do not think I’ve read through something like this before. So nice to find somebody with some genuine thoughts on this issue. Seriously.. thank you for starting this up. This site is one thing that is required on the internet, someone with a little originality!

I’m asked to do conceptual, theoretical and empirical literature, and i just don’t know how to structure it

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How to Write a Literature Review

What is a literature review.

• What Is the Literature
• Writing the Review

A literature review is much more than an annotated bibliography or a list of separate reviews of articles and books. It is a critical, analytical summary and synthesis of the current knowledge of a topic. Thus it should compare and relate different theories, findings, etc, rather than just summarize them individually. In addition, it should have a particular focus or theme to organize the review. It does not have to be an exhaustive account of everything published on the topic, but it should discuss all the significant academic literature and other relevant sources important for that focus.

This is meant to be a general guide to writing a literature review: ways to structure one, what to include, how it supplements other research. For more specific help on writing a review, and especially for help on finding the literature to review, sign up for a Personal Research Session .

The specific organization of a literature review depends on the type and purpose of the review, as well as on the specific field or topic being reviewed. But in general, it is a relatively brief but thorough exploration of past and current work on a topic. Rather than a chronological listing of previous work, though, literature reviews are usually organized thematically, such as different theoretical approaches, methodologies, or specific issues or concepts involved in the topic. A thematic organization makes it much easier to examine contrasting perspectives, theoretical approaches, methodologies, findings, etc, and to analyze the strengths and weaknesses of, and point out any gaps in, previous research. And this is the heart of what a literature review is about. A literature review may offer new interpretations, theoretical approaches, or other ideas; if it is part of a research proposal or report it should demonstrate the relationship of the proposed or reported research to others' work; but whatever else it does, it must provide a critical overview of the current state of research efforts. 

Literature reviews are common and very important in the sciences and social sciences. They are less common and have a less important role in the humanities, but they do have a place, especially stand-alone reviews.

Types of Literature Reviews

There are different types of literature reviews, and different purposes for writing a review, but the most common are:

• Stand-alone literature review articles . These provide an overview and analysis of the current state of research on a topic or question. The goal is to evaluate and compare previous research on a topic to provide an analysis of what is currently known, and also to reveal controversies, weaknesses, and gaps in current work, thus pointing to directions for future research. You can find examples published in any number of academic journals, but there is a series of Annual Reviews of *Subject* which are specifically devoted to literature review articles. Writing a stand-alone review is often an effective way to get a good handle on a topic and to develop ideas for your own research program. For example, contrasting theoretical approaches or conflicting interpretations of findings can be the basis of your research project: can you find evidence supporting one interpretation against another, or can you propose an alternative interpretation that overcomes their limitations?
• Part of a research proposal . This could be a proposal for a PhD dissertation, a senior thesis, or a class project. It could also be a submission for a grant. The literature review, by pointing out the current issues and questions concerning a topic, is a crucial part of demonstrating how your proposed research will contribute to the field, and thus of convincing your thesis committee to allow you to pursue the topic of your interest or a funding agency to pay for your research efforts.
• Part of a research report . When you finish your research and write your thesis or paper to present your findings, it should include a literature review to provide the context to which your work is a contribution. Your report, in addition to detailing the methods, results, etc. of your research, should show how your work relates to others' work.

A literature review for a research report is often a revision of the review for a research proposal, which can be a revision of a stand-alone review. Each revision should be a fairly extensive revision. With the increased knowledge of and experience in the topic as you proceed, your understanding of the topic will increase. Thus, you will be in a better position to analyze and critique the literature. In addition, your focus will change as you proceed in your research. Some areas of the literature you initially reviewed will be marginal or irrelevant for your eventual research, and you will need to explore other areas more thoroughly. 

Examples of Literature Reviews

See the series of Annual Reviews of *Subject* which are specifically devoted to literature review articles to find many examples of stand-alone literature reviews in the biomedical, physical, and social sciences. 

Research report articles vary in how they are organized, but a common general structure is to have sections such as:

• Abstract - Brief summary of the contents of the article
• Introduction - A explanation of the purpose of the study, a statement of the research question(s) the study intends to address
• Literature review - A critical assessment of the work done so far on this topic, to show how the current study relates to what has already been done
• Methods - How the study was carried out (e.g. instruments or equipment, procedures, methods to gather and analyze data)
• Results - What was found in the course of the study
• Discussion - What do the results mean
• Conclusion - State the conclusions and implications of the results, and discuss how it relates to the work reviewed in the literature review; also, point to directions for further work in the area

Here are some articles that illustrate variations on this theme. There is no need to read the entire articles (unless the contents interest you); just quickly browse through to see the sections, and see how each section is introduced and what is contained in them.

The Determinants of Undergraduate Grade Point Average: The Relative Importance of Family Background, High School Resources, and Peer Group Effects , in The Journal of Human Resources , v. 34 no. 2 (Spring 1999), p. 268-293.

This article has a standard breakdown of sections:

• Introduction
• Literature Review
• Some discussion sections

First Encounters of the Bureaucratic Kind: Early Freshman Experiences with a Campus Bureaucracy , in The Journal of Higher Education , v. 67 no. 6 (Nov-Dec 1996), p. 660-691.

This one does not have a section specifically labeled as a "literature review" or "review of the literature," but the first few sections cite a long list of other sources discussing previous research in the area before the authors present their own study they are reporting.

• Next: What Is the Literature >>
• Last Updated: Jan 11, 2024 9:48 AM
• URL: https://libguides.wesleyan.edu/litreview

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Introduction to Literature Reviews

Introduction.

• Step One: Define
• Step Two: Research
• Step Three: Write
• Suggested Readings

A literature review is a written work that :

• Compiles significant research published on a topic by accredited scholars and researchers;
• —Surveys scholarly articles, books, dissertations, conference proceedings, and other sources;
• —Examines contrasting perspectives, theoretical approaches, methodologies, findings, results, conclusions.
• —Reviews critically, analyzes, and synthesizes existing research on a topic; and,
• Performs a thorough “re” view, “overview”, or “look again” of past and current works on a subject, issue, or theory.

From these analyses, the writer then offers an overview of the current status of a particular area of knowledge from both a practical and theoretical perspective.

Literature reviews are important because they are usually a  required  step in a thesis proposal (Master's or PhD). The proposal will not be well-supported without a literature review. Also, literature reviews are important because they help you learn important authors and ideas in your field. This is useful for your coursework and your writing. Knowing key authors also helps you become acquainted with other researchers in your field.

Look at this diagram and imagine that your research is the "something new." This shows how your research should relate to major works and other sources.

Olivia Whitfield | Graduate Reference Assistant | 2012-2015

• Next: Step One: Define >>
• Last Updated: Jun 28, 2023 5:49 PM
• URL: https://libraryguides.missouri.edu/literaturereview

Literature Reviews

Introduction

Searching the literature

Critical reading, writing your review, citing and referencing.

• Further assistance

What is a Literature Review?

A literature review investigates and appraises existing knowledge, research, material and sources that have been published on a particular topic.  It can serve as a framework that informs the development and focus of an ensuing study, such as a thesis, article or research report. It can also be a stand-alone piece of research, such as an essay or conceptual article.

Literature reviews provide analyses that demonstrate a deep understanding of the existing literature, and commonly identify gaps and areas for future research to examine.  Importantly, literature reviews are diverse in their format and purpose:

• A literature review may be undertaken with a strong focus on critical evaluation, while others may adopt a more descriptive and exploratory approach.
• Some reviews concentrate on data, findings and methodologies, others examine ideas, themes, and theories.
• A review may aim to be summative in comprehensively synthesising all known literature on a topic. Other reviews may attempt to be more integrative in exploring related and interdisciplinary literatures.

This guide recognises the diversity of literature reviews. Rather than listing prescriptive advice, it aims to provide general guidance on the literature review process and share resources with you to help you get started.

Writing an Annotated Bibliography?

An annotated bibliography is a list of citations (articles, books, or other resources), each followed by a short descriptive paragraph that summarises the source's content and evaluates its relevance to the topic in question. For more information on how to write an annotated bibliography:

Visit the Academic Skills resource "Writing an annotated bibliography"

Writing a Systematic Review?

A systematic review appraises the literature in relation to a clearly-formulated question. It generally follows a strict protocol, with well-defined inclusion and exclusion criteria for the literature, data or studies assessed in the review, to ensure the transparency and reproducibility of the conclusions drawn by the review. To find out more about systematic reviews:

Visit the Systematic Reviews library guide

Strategies for an effective and comprehensive literature search

Maximise the quality, scope and appropriateness of the literature you review. When commencing a search:

• Determine key concepts and issues surrounding them
• Establish terminology so you can develop lists of key words and synonyms to use in your search
• Encyclopedias and key articles will often introduce topics and provide lists of key references

Reviewing a good range of the available literature on your topic is an important consideration. The tips below may be useful in helping you search for literature, and decide what literature to include in the scope of your review: 

• Consider the age of resources as appropriate for your review
• Use a variety of resources - books, journal articles, theses, conference papers and reports
• Search by keyword, subject, and also author
• Evaluate the information - is a journal refereed (peer-reviewed)? Is a source authoritative?
• Develop good referencing skills
• You can broaden your search by looking laterally for literature in related fields

Online guides that may help with your literature search

Research Essentials

Want to revisit the fundamentals of library research? The Research Essentials guide is a good starting point.

Finding Theses

Looking for examples of other theses to learn from and be inspired? The Finding Theses guide is highly recommended, especially for PhD students.

Staying Current

Want to keep up-to-date with the latest research? Visit the Staying Current guide for tips and tricks to setup alerts and manage information flows for you as a researcher.

Some things to consider before you start reading

• Keep your purpose in mind when you read
• Don't let the arguments in the text distract you
• Before beginning to read, take a few moments to think about what it is you are expecting from the article or chapter
• Skim-read the abstract, headings, conclusion, and the first sentence of each paragraph. Do you need to read everything with equal attention? Can you see where the arguments are headed?

Suggested critical questions to ask as you read

• What were the authors trying to discover?
• Why is this piece of research important?
• What was measured?
• What information do you have on the sample?
• How was the data collected?
• What were the results?
• What do the authors conclude and to what do they attribute their findings?
• Can you accept the findings as true?
• How can you apply these findings to your own work?

When results are conflicting, you might find it useful to ask the following questions:

• How similar were the programs used?
• Were different measurement instruments used?
• How were the programs evaluated?

Looking to improve your critical reading and notetaking skills?

Visit the Academic Skills "Reading and notetaking resources"

Structure of the review

The structure of your literature review will be based largely on your discipline and your topic. Your review is also influenced by how you decide to organise your argument(s):

• Chronological/historical
• Major authors/key studies
• Perspectives or positions taken on the topic under study
• Issues or debates (key issues/related issues)
• Methodological focus, etc.

Suggestions for structure

Organise your literature review according to an approach that best fits your topic. This means that you should not be too attached to an idea or template of how the literature review should ‘look’; instead, seek out effective models of literature reviews written in your discipline area. Broadly, the structure of a review may comprise the following elements:

• Provide an overview of the contents of the review. What is the significance and importance of the review?

Body (i.e. where you critically analyse the relevant literature)

• Synthesise the essence of literature that has dealt with your topic
• Consider any gaps or deficiencies, any inconsistencies or conflicting viewpoints and the broader implications of all this knowledge for your topic
• Draw together the important points and briefly explain how the information you have found addresses your original research question
• Indicate if more research is needed.

Important considerations

• Set parameters (e.g. inclusion and exclusion criteria for the literature referred to, date range)
• Make sure your literature review is a critical synthesis of the information you have discovered, and not just a summary
• Organise the material logically
• Make your purpose clear
• Emphasise recent/current research and developments
• Amount of detail around an issue is proportional to its importance
• Your own voice needs to be strong throughout the literature review - it needs to introduce and guide the reader through the research that is presented in the literature
• Provide commentary on design, methodology, conflicting arguments, and lack of conclusions
• Make sure citations and references are correct and accurate.

Any material you get from a source, even if you write it in your own words, needs to have a citation or footnote. Check the guidelines for your literature review, or speak to your supervisor, to determine which citation style you should be using.

Need help with your referencing? Click on the button below:

Visit the Re:Cite guide to referencing

Learn how reference management software can help you with referencing:

Visit the Options for Managing References guide

This section helps you find books and other resources which will help you write literature reviews.

Visit the Academic Skills "Reviewing the literature" page to find additional resources

Searching the resources

Use the following platforms to find resources on literature reviews:

Library Catalogue

Google Scholar

SAGE Knowledge

SAGE Research Methods Core

Search with keyword combinations such as:

"literature review*"

Create more searches by combining these keywords with the name of your discipline or subject area. For example:

(business OR economics)

writ* AND "literature review*"

architecture

writing  AND  "literature review*"

Also click on the following subject heading searches in the library catalogue:

Research - Methodology - Handbooks, Manuals, etc

Research - Evaluation

Suggested texts on academic writing

Other web-based resources

Academic skills  .

Contact Academic Skills for help with academic writing, critical reading and assessment planning.

The Library 

Contact the Library for help with finding research resources.

• Last Updated: Apr 8, 2024 4:21 PM
• URL: https://unimelb.libguides.com/lit_reviews

• Academic Skills
• Reading, writing and referencing
• Literature reviews

Writing a literature review

Find out how to write a lit review.

What is a literature review ?

A literature review explores and evaluates the literature on a specific topic or question. It synthesises the contributions of the different authors, often to identify areas that need further exploration.

You may be required to write a literature review as a standalone document or part of a larger body of research, such as a thesis.

• The point of a standalone literature review is to demonstrate that you have read widely in your field and you understand the main arguments.
• As part of a thesis or research paper, the literature review defines your project by establishing how your work will extend or differ from previous work and what contribution it will make.

What are markers looking for?

In the best literature reviews, the writer:

• Has a clear understanding of key concepts within the topic.
• Clarifies important definitions and terminology.
• Covers the breadth of the specific topic.
• Critically discusses the ideas in the literature and evaluates how authors present them.
• Clearly indicates a research gap for future enquiry.

How do I write a literature review?

This video outlines a step by step approach to help you evaluate readings, organise ideas and write critically. It provides examples of how to connect, interpret and critique ideas to make sure your voice comes through strongly.

Tips for research, reading and writing

You may be given a specific question to research or broad topics which must be refined to a question that can be reasonably addressed in the time and word limit available.

Use your early reading to help you determine and refine your topic.

• Too much literature? You probably need to narrow your scope. Try to identify a more specific issue of interest.
• Not enough literature? Your topic may be too specific and needs to be broader.

Start with readings suggested by your lecturers or supervisors. Then, do your own research - the best place to go is the Library Website .

You can also use the Library Guides or speak to a librarian to identify the most useful databases for you and to learn how to search for sources effectively and efficiently.

Cover the field

Make sure your literature search covers a broad range of views and information relevant to your topic. Focussing on a narrow selection of sources may result in a lack of depth. You are not expected to cover all research and scholarly opinions on your topic, but you need to identify and include important viewpoints. A quality literature review examines and evaluates different viewpoints based on the evidence presented, rather than providing only material that reinforces a bias.

Use reading strategies

Survey, skim and scan to find the most relevant articles, and the most relevant parts of those articles. These can be re-read more closely later when you have acquired an overview of your topic.

Take notes as you read

This helps to organise and develop your thoughts. Record your own reactions to the text in your notes, perhaps in a separate column. These notes can form the basis of your critical evaluation of the text. Record any facts, opinions or direct quotes that are likely to be useful to your review, noting the page numbers, author and year.

Stop reading when you have enough

This depends on the word count required of this literature review. A review of one thousand words can only cover the major ideas and probably less than ten references. Longer reviews that form part of a large research paper will include more than fifty. Your tutor or supervisor should be able to suggest a suitable number.

As you read, ask yourself these questions:

• Have I answered my question without any obvious gaps?
• Have I read this before? Are there any new related issues coming up as I search the literature?
• Have I found multiple references which cover the same material or just enough to prove agreement?

There are many possible ways to organise the material. For example:

• chronologically
• by theoretical perspective
• from most to least important
• by issue or theme

It is important to remember that you are not merely cataloguing or describing the literature you read. Therefore, you need to choose an organisation that will enable you to compare the various authors' treatment of ideas. This is often best achieved by organising thematically, or grouping ideas into sets of common issues tackled in the various texts. These themes will form the basis of the different threads that are the focus of your study.

A standalone literature review

A standalone literature review is structured much like an academic essay.

• Introduction - establish the context for your topic and outline your main contentions about the literature
• Main body - explain and support these inferences in the main body
• Conclusion - summarise your main points and restate the contention.

The main difference between an essay and this kind of literature review is that an essay focuses on a topic and uses the literature as a support for the arguments. In a standalone literature review, the literature itself is the topic of discussion and evaluation. This means you evaluate and discuss not only the informational content but the quality of the author’s handling of the content.

A literature review as part of a larger research paper?

As part of a larger research paper, the literature review may take many forms, depending on your discipline, your topic and the logic of your research. Traditionally, in empirical research, the literature review is included in the introduction, or a standalone chapter immediately following the introduction. For other forms of research, you may need to engage more extensively with the literature and thus, the literature review may spread over more than one chapter, or even be distributed throughout the thesis.

Start writing early. Writing will clarify your thinking on the topic and reveal any gaps in information and logic. If your ideas change, sections and paragraphs can be reworked to change your contentions or include extra information.

Similarly, draft an overall plan for your review as soon as you are ready, but be prepared to rework sections of it to reflect your developing argument.

The most important thing to remember is that you are writing a review . That means you must move past describing what other authors have written by connecting, interpreting and critiquing their ideas and presenting your own analysis and interpretation.

Looking for one-on-one advice?

Get tailored advice from an Academic Skills Adviser by booking an Individual appointment, or get quick feedback from one of our Academic Writing Mentors via email through our Writing advice service.

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Preparing to Write the Literature Review: Introduction

• Introduction
• Keyword Search vs. Subject Search
• Advanced Searching PlayList

If You Are New to Research

• Introduction to Research by Research Assistance Last Updated Jan 6, 2023 62 views this year

What is the "Literature"?

The "literature" is the body of scholarly work in any given field.

If your browser does not display frames, please use the direct link to the video provided on this page.

• What is the "Literature"? Direct link to video tutorial.

What is a Literature Review?

A literature review surveys scholarly articles, books, dissertations, and conference proceedings relevant to your research problem, providing a description, summary, and critical evaluation of each work.

Purpose of the literature review:

• Provides a historical background for your research problem
• Describes its current status
• Supports the purpose of the study
• Identifies gaps in the literature
• Become aware of variables relevant to the problem
• Understand the seminal studies widely cited
• Identifies the leading scholars relevant to the problem  

(Lunenburg, 2008)

Things to Know

Three important things to know about research

• Start early: the library has thousands of books and articles online. If we don’t have what you need, we will get it for you, but this process takes about a week.
• Be prepared: bring a flash drive with you always so you can save what you find, OR use a citation manager.
• Take notes about how you found your results! Maybe keep a “research journal.”

Literature Reviews vs. Original Research

Nearly every scholarly research article begins with a brief, basic review of existing literature. This review introduces the subject being investigated and what is already known about it, in order to provide context for the author's new research.

Check the "Introduction" section of this original research article for an example: 

• Characterisation of Mainstream and Passive Vapors Emitted by Selected Electronic Cigarettes

There is also a whole category of scholarly articles known as literature reviews. (Generally, these will use words like "Literature Review," "Review," or "Review of the Literature" right in the title.) These articles do not conduct new research, but only review existing research on some subject, in order to summarize the current state of knowledge and help other researchers exploring the same topic.

An example of a Literature Review article:

• "Inner Ear Damage Following Electric Current and Lightning Injury: a Literature Review"

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• Writing Literature Reviews (UNC)
• The Literature Review: A Few Tips On Conducting It
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Literature review.

• Introduction to Literature Reviews
• Purpose and Scope
• Types of Lit Reviews
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Literature review defined.

A Literature Review or “A Review of the Literature” is a survey of existing scholarly writings or published knowledge on a particular topic. It is not an analysis of a single work of literature (e.g. analysis of Moby Dick ) but rather a survey, summary, critical analysis, comparison, and synthesis of multiple scholarly works addressing a specific subject area.

Conducting a literature review is part of the research process and serves to establish a base of knowledge and overview of the principle works on a specific area of research as well as identify important themes, discoveries, areas of consensus and debate, changes over time, and provide a foundation for further research. There are multiple lit review types and methodologies which vary by discipline and the particular requirements of your assignment.

Why Write a Literature Review?

What is the purpose of a literature review? It is probable that at some point in your professional career inside or outside of academia you will be required to undertake a literature review.  A lit review may be required as part of any research proposal such as a senior thesis or dissertation or as part of a grant application. Many professions utilize lit reviews prior to implementation of important projects.

Lit reviews are also critical in fields which experience rapid change and require knowledge of the most current research and practice. And of course personal curiosity is as good a reason as any!

This guide will show you how to :

• find existing lit reviews
• help you to start writing your own lit review
• and point you to other helpful sources
• Next: Purpose and Scope >>
• Last Updated: Dec 15, 2023 1:47 PM
• URL: https://utopia.ut.edu/literaturereviews

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Article Contents

Introduction, acknowledgments, supporting information, mapping the evidence of novel plant-based foods: a systematic review of nutritional, health, and environmental impacts in high-income countries.

• Article contents
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Sarah Nájera Espinosa, Genevieve Hadida, Anne Jelmar Sietsma, Carmelia Alae-Carew, Grace Turner, Rosemary Green, Silvia Pastorino, Roberto Picetti, Pauline Scheelbeek, Mapping the evidence of novel plant-based foods: a systematic review of nutritional, health, and environmental impacts in high-income countries, Nutrition Reviews , 2024;, nuae031, https://doi.org/10.1093/nutrit/nuae031

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Shifting from current dietary patterns to diets rich in plant-based (PB) foods and lower in animal-based foods (ABFs) is generally regarded as a suitable strategy to improve nutritional health and reduce environmental impacts. Despite the recent growth in supply of and demand for novel plant-based foods (NPBFs), a comprehensive overview is lacking.

This review provides a synthesis of available evidence, highlights challenges, and informs public health and environmental strategies for purposeful political decision-making by systematically searching, analyzing, and summarizing the available literature.

Five peer-reviewed databases and grey literature sources were rigorously searched for publications.

Study characteristics meeting the inclusion criteria regarding NPBF nutrient composition and health and environmental outcomes in high-income countries were extracted.

Fifty-seven peer-reviewed and 36 grey literature sources were identified; these were published in 2016–2022. NPBFs typically have substantially lower environmental impacts than ABFs, but the nutritional contents are complex and vary considerably across brands, product type, and main primary ingredient. In the limited evidence on the health impacts, shifts from ABFs to PB meats were associated with positive health outcomes. However, results were mixed for PB drinks, with links to micronutrient deficiencies.

If carefully selected, certain NPBFs have the potential to be healthier and nutrient-rich alternatives to ABFs and typically have smaller environmental footprints. More disaggregated categorization of various types of NPBFs would be a helpful step in guiding consumers and key stakeholders to make informed decisions. To enable informed policymaking on the inclusion of NPBFs in dietary transitions as part of a wider net-zero and health strategy, future priorities should include nutritional food standards, labelling, and subdivisions or categorizations of NPBFs, as well as short- and long-term health studies evaluating dietary shifts from ABFs to NPBFs and standardized environmental impact assessments, ideally from independent funders.

The fragile interconnection between food systems and the environment is increasingly evident. 1–3 While current agricultural practices are damaging the environment, environmental change is putting food supplies at risk of disruption if timely adaptation strategies are not used. 4–8 This relationship exists at a time when food systems are already struggling to provide healthy diets for all, with many populations experiencing a coexistence of undernutrition and obesity. 1 , 3

Structural changes in food systems are critical to both safeguard people’s health and accomplish the climate adaptation and mitigation commitments mentioned in The United Nations Framework Convention on Climate Change 9 and the United Nations’ Sustainable Development Goals. 10 While production-side strategies can contribute toward climate mitigation, substantial opportunities for further emission reductions and acceleration toward net-zero targets can be achieved through dietary changes and the resulting lower demand for foods with a large environmental footprint.

In food-secure and high-income settings, a shift from “conventional diets” (which typically contain high amounts of animal-based foods [ABFs]) to predominantly plant-based (PB) diets could improve population and planetary health. 2 , 11 Dietary change has many obstacles, with diets influenced by many factors 12 , 13 that act as barriers to increasing consumption of minimally processed PB foods (eg, legumes, vegetables). If common barriers are removed, such as the need for additional cooking skills, major changes in taste and appearance of commonly consumed dishes, and fear of social stigma, 14 , 15 novel plant-based foods (NPBFs), products designed to mimic and replace ABFs to allow easy incorporation into habitual diets (eg, vegan and vegetarian meat and dairy) (see Box 1 ), may offer an easier option to facilitate this shift.

In recent years, the NPBF landscape has expanded rapidly. Several new types of NPBFs (eg, PB drinks, yogurts, eggs, meats) were introduced to the market, and trends showed increasing sales, volume, and investment growth across many countries. 16–21 In 2023, data suggested a possible slowdown, especially for PB meats, with some consumers criticizing their cost and taste, 22 and some NPBF manufacturers reporting net losses. 23 , 24 However, sales of supermarkets’ own-label PB meat alternatives have seen growth, 23 alongside consistent increases in sales of PB dairy and eggs 25 (see Supplementary file 1, section 1.1, in the Supporting Information online for detailed information on costs).

According to a global survey focusing on individuals following vegan or vegetarian diets most or all of the time, 22.0% of consumers reported adhering to a meat-free diet, and there is growing interest in embracing PB eating, with approximately 42.0% of consumers anticipating that PB foods will replace most meat within a decade. 26 With consumption of NPBFs in the United Kingdom doubling between 2008 and 2019, particularly among women and younger generations, and the fact that in 2022, 60.0% of US households purchased at least 1 type of NPBF, verification of any health and sustainability claims in marketed products is of vital importance. 22 , 27 , 28 Currently, various NPBFs are advertised as potential dietary “game changers,” with claims that they would play an important and positive role in sustainability and health, 29 , 30 and, thus, could play a pivotal role in the so-called consumption corridors. 31 However, because of their novelty, some consumers question these positive claims. 32 Although NPBFs are generally regarded as a low-carbon alternative to ABFs, their nutrient and health profiles remain largely unknown and are often criticized. This is primarily related to concerns regarding micronutrient and protein content, along with higher content of saturated fats and sodium in comparison to ABFs, and level of processing. 33 , 34

Previous reviews have primarily focused on single aspects of NPBFs 17 , 19 , 22 , 25 , 29 , 34–46 or ingredients of NPBFs 39 , 47–50 ; a few recent reviews explored the positive health and environmental outcomes of consuming selected NPBFs. 51–53 However, research quantifying the potential impacts of NPBFs is still in its infancy, and an overview that is both systematic and comprehensive, comprising health, nutrient, and environmental outcomes from peer-reviewed and grey literature of different types of NPBFs, does not yet exist, to our knowledge. This lack makes it difficult for policy makers and consumers to assess the trade-offs between nutrient composition and the environmental and health impacts of NPBFs, and hinders the potential inclusion of NPBFs in sustainable and healthy dietary recommendations.

To synthesize available evidence, highlight challenges, inform public health and environmental strategies, and inform purposeful political decision-making, we aimed, in this study, to systematically search, analyze, and summarize the available grey and peer-reviewed literature on the nutrient composition, environmental footprints, and health effects of NPBFs sold and consumed in high-income countries, and to quantify and summarize their reported results.

The full-study protocol we followed is published elsewhere (see Nájera Espinosa et al 54 and Supplementary file 1, section 2, in the Supporting Information online for more details on the methods). Briefly, a systematic search was performed to identify peer-reviewed journal articles and grey literature that contained data on the nutrient composition, health impacts, and environmental impacts of NPBFs. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. 55

Peer-reviewed literature

Five scientific databases were systematically searched (MEDLINE, Embase, Global Health, GreenFILE, and the Web of Science Core Collection) on August 29, 2021; we conducted an updated search on June 29, 2022. The search was limited to articles published and accepted after January 2016 until June 29, 2022, because of the substantial growth in supply and demand of NPBFs in the past 7 years. 16–19 In addition to database searching, citation lists from identified systematic literature reviews were handsearched (see Supplementary file 1, section 2.6, in the Supporting Information online for the full search strategy). After the quality criteria were applied (described in Supplementary file 1 , Table S1 in the Supporting Information online ), titles were manually and triple screened. Abstracts were manually double screened after application of a supervised machine-learning algorithm (ie, a support vector machine 56 ) through Scikit Learn 57 that ranked and highlighted likely relevant articles (ie, conducted priority screening). This approach is described elsewhere in detail (see Supplementary file 1, section 2.1, in the Supporting Information online ). 58 Full texts were manually screened by 2 authors and data were also double extracted.

Grey literature

To capture grey literature in a systematic way, a manual search was conducted on Google (see Supplementary file 1, section 2.3 , and Table S3 in the Supporting Information online ). Text from the webpages was then scraped and a state-of-the-art, pretrained language model from Hugging Face 59 was used to create a summary of each web link. Results were exported into a comma-separated value, or CSV, file. Additionally, a manual search in Google of relevant websites from the top NPBF producers in the United Kingdom and United States was conducted. 60–63 And literature from relevant websites that promote NPBFs, such as the Good Food Institute and Green Queen, were searched and screened manually (see Supplementary file 1, section 2.3 , and Tables S4 and S5 in the Supporting Information online ).

Data analysis, categorization, and key definitions: nutrient, health, and environmental outcomes

The PICO (population, intervention, comparison, and outcome) criteria are defined in Table 1 (see Supplementary file 1, Table S1 in the Supporting Information online for a detailed list of the inclusion and exclusion criteria). Main study characteristics and nutrient, health, and environmental outcomes were extracted (see Supplementary files 1 and 3 in the Supporting Information online for more details).

PICO criteria for inclusion of studies

PB drinks and milk reported in 100 ml of product.

NPBFs and their ABF counterparts were categorized into food groups on the basis of their primary ingredient ( Table 2 ). See Supplementary file 1, sections 2.4 and 2.5, in the Supporting Information online for more details on the selection of nutrients, data analysis assumptions, and ABF baseline comparators). The following terms for each NPBF type are used in this review:

Food groups for novel plant-based foods and animal-based foods and their respective reported main primary ingredient

For the purposes of this review, peanuts were included in the Nuts and Seeds group because they are typically consumed as such.

Blended or mixed products, if reported, the first ingredient was taken as the primary ingredient. For example, soy & almond PB drinks were labelled as legumes.

If a product did not report any ingredients, they were categorised as unknown.

PB meat products or alternatives: include different types of PB meats (eg, PB chicken, sausages, mincemeat), categories (eg, mycoprotein, legumes), and brands

PB drink products or alternatives: include different PB drink categories (eg, legumes, nuts, seeds) and brands

PB yogurt products or alternatives: include different PB yogurt categories (eg, legumes, coconut) and brands

PB cheese products or alternatives: include different types of PB cheese categories (eg, coconut, nuts, seeds) and brands

PB egg products or alternatives: include different types of PB egg categories and brands

Mention of PB products (without further specification) refers to all the listed product subcategories mentioned, except for PB eggs.

Assessment of robustness and relevance

A modified version of the Critical Appraisal Skills Program checklist for randomized controlled trials 64 was adapted to assess robustness and relevance of the studies in the full-text reviewing stage. The modifications involved the exclusion of the randomization, blinding, and cost-effectiveness criteria on the Critical Appraisal Skills Program checklist, and funding source was added as a criterion. Studies were assessed by 4 reviewers (G.H., R.P., S.P., and S.N.E.). Studies were assessed as follows: (1) clear description of the study design, (2) appropriate comparison group, (3) clear description of the methods, (4) rigorous and clearly described analysis, (5) funding source, and (6) precision of measure of effect. Studies with a minimum score of 1 were included, and sensitivity analysis was performed by funding source (see Supplementary file 1, section 2.2, in the Supporting Information online for more details).

Fruit, vegetable, legume, and nut content in novel plant-based foods

In addition to the review component, a cross-sectional analysis was conducted to examine the total fruit, vegetable, legume, and nut content (percentage estimate) of each type of NPBF sold in the United Kingdom. For this, a time-stamped data set of observations from UK supermarkets generated by FoodDB in October 2021 was used. Details are described elsewhere 65 and in Supplementary file 1, section 2.7, in the Supporting Information online . Detailed data at the global level are not available to date; hence, this part of the analysis is limited to the United Kingdom only.

Sensitivity analysis

A common concern about studies on the health impacts and environmental sustainability of NPBFs is that they can be funded by the industry that produces them; hence, we conducted a sensitivity analysis by funding source. Furthermore, given that relative improvements in health and environmental sustainability depend on the baseline comparator used ( Supplementary file 1, section 2.2, in the Supporting Information online ), the sensitivity analysis based on the main primary ingredient of a given NPBF and its respective ABF comparator was also performed. The Wilcoxon test for sensitivity analysis with a significance level set at P  ≤ 0.05 was used.

Systematic search results

A total of 49 563 peer-reviewed and 891 grey literature records were identified from the initial search. After unique literature sources were screened, 57 peer-reviewed articles and 36 grey literature studies met the inclusion criteria ( Figure 1 ). Supplementary 1, section 2, in the Supporting Information online provides further details on the screening process. The study characteristics that were extracted included basic study details (eg, authors, year, type of study, country, number of participants, follow-up period), relevant macro- and micronutrient content (eg, those related to common deficiencies, such as iron, calcium, vitamin B 12 ), health and health proxy data (eg, obesity, micronutrient status, risk factors related to noncommunicable diseases), and environmental variables (eg, carbon, water, and land-use data).

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart of systematic review process reporting nutrient composition, and environmental and health outcomes of novel plant-based products in high-income countries . Abbreviations : IPCC, Intergovernmental Panel on Climate Change.

Nutrient composition of novel plant-based foods

The nutrient content of NPBFs was the most frequently studied outcome (n = 56 studies). Nutrient data were typically collected through supermarket cross-sectional surveys or manufacturers’ websites. PB meat alternatives (n = 35) and PB drink alternatives (n = 19) were most frequently reported; fewer studies researched PB cheese (n = 5) and yogurt alternatives (n = 4). No studies were found that assessed PB egg alternatives. The nutritional profile of NPBFs varied greatly by manufacturing process, including the main base ingredient (eg, soy, almond); the processing techniques, time, and temperature applied; and the type of product manufactured (ie, PB drinks, PB meats). 39 , 40 , 66 , 67

Energy density, saturated fat, fiber, sugar, sodium, and micronutrient content of plant-based meat alternatives

The 35 publications evaluating PB meat alternatives reported on 508 PB meat products with 66 ABF comparators. Where the median values for meat comparators were reported to be 221.0 kcal/100 g (interquartile range [IQR], 186.6–246.7), 5.7 g/100 g saturated fat (IQR, 3.2–7.1), and very low fiber (<0.1 g/100 g; IQR, 0.0–0.5), most meat-alternative groups were reported to have lower energy density, lower saturated-fat content, and more fiber ( Figure 2 and Supplementary file 2: Table S1 for detailed macronutrient information disaggregated by main ingredient). Mycoprotein-based meat alternatives were reported to be the least energy dense, with a median energy value of 123.0 kcal/100 g (IQR, 94.0–198.5; with ABFs, P value of difference [ P d ] < 0.001), whereas meat alternatives based on cereals and grain had the highest energy density of all PB meats (226.0 kcal/100 g [IQR, 189.8–268.5]; P d < 0.360), with values very similar to those of meat and poultry. Mycoprotein-based meats were also reported to be lowest in saturated fat (0.8 g/100 g [IQR, 0.5–1.3]; P d < 0.001), whereas nut- and seed-based meats had the highest saturated fat content (1.4 g/100 g [IQR, 1.1–1.7]; P d = 0.003) of all PB meats, which still was significantly lower than saturated fat content in meat and poultry. Finally, mycoprotein-based meat was reported to contain the highest fiber content (median, 6.0 g/100 g [IQR, 5.2–7.1]; P d  < 0.001), whereas cereal- and grain-based meats had the lowest fiber content of all PB meats (3.1 g/100 g [IQR, 2.3–3.9]; P d < 0.001), which still was significantly higher than in meat and poultry.

Macronutrient, sodium, and energy content in plant-based meat and drink alternatives in their respective food group based on main primary ingredient   (ie, predominant or core food item on the ingredient list) compared with meat and poultry, and dairy, respectively . Data were limited to raw products only. Abbreviation : M, median of each category.

Meat and poultry contained a median of 0.5 g/100 g total sugar (IQR, 0.0–0.9) and 426.7 mg/100 g sodium content (IQR, 101.0–672.8). All PB meats contained more total sugar but had similar levels of sodium in comparison with meat and poultry. Mycoprotein-based meats had the lowest total sugar content of all PB meats (median, 0.8 g/100 g [IQR: 0.5–1.8]; P d < 0.001], and nut- and seed-based meats contained the highest total sugar amount (median, 4.2 g/100 g [IQR, 2.3–6.6]; P d = 0.002); both showed strong evidence of being higher in total sugar content than meat and poultry. This is equivalent to 0.4 g and 3.4 g of total sugar/80.0 g serving size, or, if these sugars are considered free, 1.6% and 13.4% of the maximum recommended approximately 25.0 g average daily sugar intake. 68 Finally, the median sodium values for all PB meat groups did not show strong evidence of a difference from meat and poultry, except for legume-based meats (median, 520.0 mg/100 g [IQR, 400.0–636.0]; P d = 0.011). This is equivalent to 416.0 mg of sodium (or 1.0 g of salt) per 80.0 g serving size, or 20.8% of the maximum recommended 5.0 g average daily salt intake. Moreover, there were extreme outliers, with some PB meats reported to contain more than 1400.00 mg sodium (equivalent to 2.8 g salt) per 80.0 g; thus, consumption of 1 portion of this PB meat alternatives is more than half the recommended maximum daily intake of salt. 69

Only a few studies (n = 9) evaluated micronutrient data; these reported on 250 PB meat products and 24 ABF comparators. Micronutrient content ranged vastly across all groups: whereas some products would provide substantial contributions to average daily requirements, others were much less nutritious ( Table 3 and Supplementary file 2: Table S2 ). 69–83 For example, the median iron content for cereal- and grain-based PB meats (5.4 mg/100 g [IQR, 4.2–5.4]) was higher than the median of meat and poultry (1.3 mg/100 g [IQR, 1.1–1.6]). On the contrary, vitamin B 12 levels were lower for PB meat alternatives (medians ranged from 0.1 μg/100 g [IQR: 0.0–0.9] to 0.3 μg/100 g [IQR: 0.3–0.3]) as compared with 1.2 μg/100 g (IQR: 0.6–1.6) in meat and poultry. However, certain individual products had a comparable or higher vitamin B 12 content than their ABF comparator.

Summarized micronutrient values for PB meat and drinks and animal-based foods a

Values are compared with global average daily requirements (see Supplementary file 2 in the Supporting Information online for detailed information containing all disaggregated numbers by main ingredient of each novel plant-based food and animal-based foods). The table only reports micronutrients commonly found in meat and dairy. PB products also provided other micronutrients not commonly found in meat and dairy (ie, calcium in PB meats).

Abbreviations : ADR, average daily requirement; max, maximum; min, minimum; IQR, interquartile range; PB, plant-based.

No studies reported nutrient data from organic products. Although protein levels were not the main focus of this study, protein results are reported in Supplementary file 1: Figure S2 and Supplementary file 2: Table S1 , and show that, particularly, legume- and mycoprotein-based PB meats typically match meat and poultry in protein content.

Energy density, saturated fat, fiber, sugar, sodium, and micronutrient content of plant-based drinks

The 19 studies evaluating PB drinks reported on 397 PB drinks (unflavored and unsweetened) and 52 dairy milk products. Where dairy milk comparators were reported to contain median values of 50.1 kcal/100 mL energy density (IQR, 39.3–63.0), 1.1 g/100 mL saturated fat (IQR, 0.9–2.2), and no fiber (0.0 g/100 mL; IQR, 0.0–0.0), most PB drink groups were reported to have lower energy density, lower saturated fat content, and more fiber ( Figure 2 and Supplementary file 2: Table S1 ). Coconut-based drinks were reported to be the least energy dense (median energy value, 20.0 kcal/100 g [IQR: 19.0–33.7]; P d < 0.001), whereas drinks based on cereals and grains had the highest energy density of all PB drinks (median, 59.0 kcal/100 mL [IQR: 43.0–57.0]; P d = 0.566) but not significantly higher than dairy milks. PB drinks made of cereals and grains, fruits and vegetables, and nuts and seeds were reported to be lowest in saturated fat (median, 0.2 g/100 mL; IQRs, 0.1–0.2, 0.2–0.2, and 0.1–0.3, respectively; P d < 0.001), whereas coconut-based drinks had the highest saturated fat content (median, 1.1 g/100 mL; IQR, 0.9–1.7; P d = 0.952) of all PB drinks, but this was not significantly different than dairy milks. All PB drinks contained more fiber than dairy milks; however, only the drinks based on cereals and grains, legumes, and nuts and seeds were significantly higher in fiber when compared with dairy milks (for cereals and grains, and for legumes: median, 0.5 g/100 mL [IQRs, 0.2–0.8 and 0.2–0.6, respectively]; and for nuts and seeds, 0.3 g/100 mL [IQR, 0.3–0.5]; P d < 0.001).

Dairy milks contained a median of 4.7 g/100 mL total sugar (IQR, 4.3–5.0) and 39.1 mg/100 mL sodium (IQR, 33.6–43.3). Most PB drinks contained less total sugar than did dairy milks, but they had similar levels of sodium. However, the total sugar content was only significantly lower for coconut (median, 1.9 g/100 mL; IQR, 1.5–2.5), legumes (median, 1.9 g/100 mL; IQR, 0.5–2.6), and nut- and seed-based drinks (median, 2.4 g/100 mL; IQR, 0.2–3.3) when compared with dairy milks ( P d < 0.001). This is equivalent to 3.8 g and 4.8 g of total sugar/200.0 mL serving size, or, if these sugars are considered free, 15.2% and 19.2% of the maximum recommended 25.0 g average daily sugar intake. 68 The only PB drink group that was statistically different in sodium content compared with dairy milks was the group based on nuts and seeds (median, 47.2 mg/100 mL [IQR, 34.0–60.0]; P d = 0.032). This is equivalent to 94.4 mg of sodium (0.2 g of salt) per 200.0 mL serving size, or 4.0% of the maximum recommended 5.0 g average daily salt intake. 69 However, there were also some extreme outliers, some of which reported containing more than 3 times this amount of sodium per 200.0 mL, the equivalent of approximately 12.0% of the daily World Health Organization recommendation. 69

A few studies (n = 16) evaluated micronutrient data of PB drinks, reporting on 249 PB alternative products and 37 ABF comparators. Iodine was only reported in PB drinks, not in other types of PB products. Like PB meat alternatives, micronutrient content ranged vastly across all groups: some products contributed to the average daily requirement, whereas others were much less nutritious ( Table 3 and Supplementary file 2: Table S2 ). For example, the median calcium content for all PB drink categories was 120.0 mg/100 mL (IQRs as follows: cereals and grains, 120.0–120.0; coconut, 120.0–120.0; fruits and vegetables, 120.0–120.0; legumes, 120.0–120.0; nuts and seeds, 114.5–120.0) as compared with 116.7 mg/100 mL (IQR, 109.3–124.0) for dairy milks. However, none of the PB products (median, 0.0 μg/100 mL; IQR, 0.0–1.4) matched the iodine content of dairy milks (median, 24.9 μg/100 mL; IQR, 20.0–36.5).

Only 4 studies (evaluating 29 PB drinks and 11 dairy milk products) reported nutrient data from organic PB products. All evaluated different nutrients, hence no further pooling of results was possible for organic products as a subgroup. Protein results are reported in Supplementary file 1: Figure S2 and Supplementary file 2: Table S1 in the Supporting Information online, which show that, particularly, legume-based PB drinks typically match dairy milk in protein content.

Energy density, saturated fat, fiber, sugar, sodium and micronutrient content of plant-based yogurt alternatives

The 4 studies on PB yogurt alternatives evaluated 191 PB yogurt products with 90 dairy-based comparator products (unflavored and unsweetened). The overall nutritional composition of PB yogurts appears to show some variation by main primary ingredient (see Supplementary file 2 in the Supporting Information online ); however, formal disaggregated assessment of PB yogurts by primary ingredient was not possible, because that information was often not reported by authors. At an aggregate level, PB yogurts typically contained less saturated fat and sodium but had a higher energy density and higher total sugar and fiber content.

Only 2 studies evaluated micronutrient data of PB yogurts (excluding sodium) and, therefore, no further pooling of results was possible. No studies reported nutrient data from organic PB yogurts. Protein results are reported in Supplementary file 2: Table S1 in the Supporting Information online . Only the sample of a legume-based PB yogurts came close to matching dairy yogurt in protein content.

Energy density, saturated fat, fiber, sugar, sodium and micronutrient content of plant-based cheese alternatives

The 5 studies evaluating PB cheese alternatives reported on 163 PB cheese products with 143 dairy-based comparator products. PB cheese alternatives were the least nutritionally diverse foods. Where the primary ingredient of PB cheeses was known, this was mostly coconut oil ( Supplementary file 2 in the Supporting Information online ); however, like PB yogurts, the main ingredient was often not reported by authors.

The cheese comparators were reported to contain median values of 284.0 kcal/100 g energy density (IQR, 108.0–330.1), 14.0 g/100 g saturated fat (IQR, 11.0–17.3), and no fiber (0.0 g/100 g; IQR, 0.0–0.0). Most PB cheese subgroups were reported to have higher energy densities and higher saturated fat and fiber content. PB cheese based on nuts and seeds had the highest energy density (328.0 kcal/100 g [IQR, 306.0–328.0]; P d = 0.334]), whereas coconut oil-based cheese had the highest saturated fat content (21.0 g/100 g [IQR, 19.7–22.0]; P d < 0.001]), a significant difference, with 50.0% more than dairy cheese. Unlike PB drinks, PB meat, and PB yogurt alternatives, not all PB cheese contained fiber. Nut- and seed-based cheese had the highest fiber content (median, 2.5 g/100 g [IQR, 2.4–2.7]; P d < 0.001). Although the median fiber content of PB cheese made from coconut oil was 0.0 g/100 g (IQR, 0.0–1.7; P d = 0.011), some products did contain up to 5.9 g/100 g and, therefore, strong evidence was found that both PB cheese based on nuts and seeds and on coconut oil had significantly higher fiber content than did dairy cheese.

Most PB cheese contained less sugar and sodium than did dairy cheese, which had a median of 2.0 g/100 g (IQR, 0.5–5.0) and 720.0 mg/100 g (IQR, 560.0–1000.0), respectively, across the identified studies. In general, PB cheese alternatives had either no or minimal total sugar content. Finally, coconut oil–based cheese had the highest sodium content across all PB cheese (median, 714.0 mg/100 g [IQR, 600.0–880.0]; P d = 0.897), but this was similar to dairy cheese. PB cheese made of nuts and seeds had the lowest median sodium content (240.0 mg/100 g [IQR, 200.0–240.0]; P d = 0.001), which would equal 48.0 mg of sodium (0.1 g of salt) per 20.0 g serving size, or 2.0% of the recommended maximum daily salt intake 69 ; hence, this type of PB cheese had a large reduction in sodium compared with dairy cheese.

The micronutrient content of PB cheese was evaluated by only 2 studies. Only 1 product made of nuts and seeds was fortified with calcium, whereas coconut-based PB cheese was typically fortified with vitamin B 12 (median, 2.5 μg/100 g; IQR, 2.5–2.5). For dairy cheeses, these medians were 815.0 mg/100 g (IQR, 463.0–930.0) for calcium and 2.5 μg/100 g (IQR, 1.8–2.5) for vitamin B 12 .

No studies reported nutrient data from organic products. Protein results are reported in Supplementary file 2: Table S1 in the Supporting Information online. Nut- and seed-based cheese typically had the highest protein content, though it did not match the protein content of dairy cheese.

Health impacts and risk factors of novel plant-based foods

Eleven peer-reviewed studies were included in this review, 9 of which evaluated PB meat alternatives and 3 evaluated PB drinks ( Table 4 ) 84–94 (see Supplementary file 1, section 3.3, in the Supporting Information online for further details on the health outcomes). No health studies were found that evaluated consumption of PB cheese, yogurt, or egg alternatives; links between NPBFs and mental health outcomes; nor any grey literature evaluating any health outcomes.

Summary of the evidence on the health impacts and risks of novel plant-based foods

Health impacts and risk factors of plant-based meat alternatives

Studies of PB meats (n = 9) showed positive health outcomes when individuals switched from consuming ABFs. Three studies on mycoprotein consumption by both healthy and overweight adults found a positive association with lower glycemic markers, 84 reduced energy intake, 84 , 85 and insulin release. 85 Moreover, mycoprotein consumption was hypothesized to have a beneficial impact on the plasma lipidome. 86

Four studies with healthy adults evaluated PB meat alternatives consumption (other than mycoprotein). When considering the same caloric intake, consumption of PB meats was associated with a lower risk of cardiovascular disease than was consumption of ABFs, mostly by reducing fasting serum levels of trimethylamine- N -oxide, and low-density lipoprotein cholesterol concentrations, compared with ABF consumption. 87 Furthermore, consumption of PB meats was associated with a reduction in body weight as compared with meat consumers. 87 , 88 Lysine-enriched PB meat as a substitute for ABFs was reported to increase muscle protein synthesis rates, which is a biological process of building new protein cells via amino acids. 89 Last, the replacement of 4 meat-containing meals per week with PB meat alternatives elicited positive changes in the gut microbiome, with changes in the presence of butyrate-producing pathways and increased taxa. 90

Health impacts and risk factors of plant-based drinks

Studies assessing PB drinks (n = 3) only focused on almond and soy drinks. The main focus and health outcomes of these studies varied. Sun et al 91 researched the reduction in glycemic response in young adults consuming soy drink or bovine milk together with white bread. These authors found that both products had a similar glycemic response through different biological pathways. Dineva et al 92 assessed micronutrient content in PB drinks and found significantly lower iodine intake and urinary iodine concentration in people consuming only PB drinks, 93 highlighting the need for appropriate fortification as more people transition to eat more NPBFs. Finally, Shen et al 93 evaluated the impact of PB drinks on dental health and found that a soy drink with added sugar caused enamel demineralization, compared with dairy milk, which promoted remineralization.

Environmental impacts of novel plant-based foods

A total of 53 studies evaluated at least 1 environmental outcome, using the life cycle assessment method, evaluating 209 PB products and 91 ABFs as comparators. Most studies used life cycle assessment inventories, and some relied on data providers (n = 32) to calculate environmental footprints. System boundaries varied across studies, with the majority evaluating category impacts from cradle-to-retail (see Supplementary file 3 in the Supporting Information online ). Studies mainly assessed the effect of substituting ABFs with NPBFs on greenhouse gas emissions (GHGE) (n = 50), followed by blue-water footprint (WF) (n = 39) and land use (LU) (n = 17) ( Figure 3 and Supplementary file 1: Table S11 in the Supporting Information online ). Although methods, assumptions, and inventory data varied from 1 study to another, most studies consistently reported percentage reductions in GHGE and LU for the production of NPBFs as compared with ABFs. Wider differences were observed in blue WF.

Reduction of environmental impacts by respective funding source . Calculated as a percentage difference between each novel plant-based (PB) product (by product type and food group based on main primary ingredient [ie, predominant or core food item on the ingredient list]) in comparison with their respective reported baseline (eg, dairy milk and cheese, meat and poultry). See Supplementary file 3 in the Supporting Information online for detailed information on the baseline used for each reference. Data were limited to raw products only. Studies reporting data on cooked PB products also found reductions in environmental impacts.

Environmental footprints of plant-based meat alternatives replacing meat and poultry

The 34 publications evaluating PB meat alternatives reported on 135 PB meat products with 53 ABF comparators. The percentage difference showed reductions of more than 70% in GHGE, LU, and WF for most products when shifting from ABFs to PB meat alternatives. GHGE reductions across PB meat groups, based on primary ingredients, were similar, with the largest reduction in GHGE seen for nut- and seed-based meats, with a median value of –94.2% (IQR, –94.4 to –93.4), whereas PB meats based on legumes had the smallest reduction (–86.1%; IQR, –88.6 to –77.5). Only 2 of 134 PB products had higher levels of GHGE than their ABF comparator. For LU, mycoprotein (median, 89.0%; IQR, –92.3 to –76.5) and nut- and seed-based meats (median, 89.5%; IQR, –90.0 to –89.0) had the largest reduction. Alternatively, legume-based meats had the smallest LU reductions (median, –71.2%; IQR, –84.7 to –47.6). Only 3 of 55 products had higher LU than their ABF comparator. Finally, the largest reduction of WF was observed in PB meats made of cereals and grains (median, –92.6%; IQR, –94.1 to –92.0), and the smallest was observed with products made of mycoprotein (median, –73.7%; IQR, –84.4 to –55.2). Nine of 51 products had a higher WF than their respective ABF counterparts. Specifically, when certain individual legume- and mycoprotein-based meats were compared with chicken, PB meat alternatives reported requiring between 2.7% and 339.0% more water, with the largest difference observed in a Swedish chicken comparator to mycoprotein-based meats. This variation was attributed to differences between feed types, rearing systems, and farm efficiency across countries. 74 Comparisons were also made between the upper limit footprint of mycoprotein-based items and the average or lower limit footprint of the ABF. Moreover, there were extreme outliers, with some PB meats reporting a water percentage difference of 8006.9%. The authors attributed this to soybeans’ substantial water demand during processing and lower yield per soybean. 74

Environmental footprints of plant-based drinks alternatives replacing dairy milk

The 21 publications evaluating PB drinks reported on 51 PB drink products with 13 ABF comparators. PB drinks also were associated with reductions in GHGE and LU when shifting from dairy milk to PB drinks. Fruit- and vegetable-based drinks had the largest reduction of GHGE (median, –90.2%; IQR, –90.8 to –90.2]), whereas PB drinks based on cereals and grains had the smallest reduction (median, –76.9%; IQR, –88.8 to –56.0). Only 2 products of 36 had an increase of GHGE when comparing soy- (40.0%) and almond-based (18.9%) drinks with dairy milk (equivalent to 0.3, 0.4, and 0.3 kg CO 2 eq/100 g, respectively). 95 Wider differences were observed on the LU percentage difference; however, reductions were found for all products (n = 13 PB drinks).

Cereal- and grain-based drinks had the largest reduction (median, –86.4%; IQR, –92.7 to –76.0), whereas legume-based drinks had the smallest LU reductions (median, –56.6%; IQR, –75.5 to –38.8). The magnitude of change in the percentage difference for WF varied considerably, although, these data were less frequently reported by authors (n = 11 PB drinks). Cereal- and grain-based drinks had the largest reduction (median, –85.0%; IQR, –88.7 to –71.0), whereas legume-based drinks had the smallest WF reductions (median, –67.6%; IQR, –73.9 to –42.2). Nut- and seed-based drinks presented contradictory evidence. For example, Grant and Hicks 95 observed that almond drinks (9241.9%) required considerably more water than soy (–35.6%) and dairy milks (equivalent to 109.3, 0.8, and 1.2 L/100 g, respectively); whereas Ritchie 96 found that an almond drink required half the amount of water (–40.87%) than dairy milk (equivalent to 37.2 and 62.8 L/100 g, respectively). Data were limited to these 2 products; hence, no further pooling of results was possible.

Environmental footprints of plant-based yogurt alternatives replacing dairy yogurt

The 2 publications evaluating 2 PB yogurt alternatives compared to 2 dairy yogurts. They reported GHGE reductions ranging between –64.7% and –52.9%. Analysis of LU and WF was not possible due to lack of a baseline, differences in methods, and system boundaries.

Environmental footprints of plant-based cheese alternatives replacing dairy cheese

The 2 publications evaluating PB cheese alternatives reported on 21 PB cheese products with 23 ABF comparators. Data on the environmental impacts were particularly from coconut oil–based cheese alternatives (n = 20). All coconut oil–based cheese alternatives had a large reduction in amounts of GHGE and LU (GHGE: median, –75.4% [IQR, –77.4 to –59.3]; LU: median, –83.1% [IQR, –83.8 to –80.6]). A smaller reduction was observed in WF (median, –45.1%; IQR, –52.0 to 38.5), with a higher WF being reported than for the ABF comparator for only 3 products.

Health effects and environmental impacts of novel plant-based foods

Studies that simultaneously assessed both health and environmental outcomes and/or nutrient profiles of NPBFs were pooled ( Figure 4 ). Only 1 study reported environmental outcomes together with diet-related health effects of PB meat alternatives, and this study found that free access to NPBFs was associated with greater weight loss and reduced dietary carbon and LU, as compared with a control arm. 88 From 93 references, 20 studies assessed the environmental outcome and nutrient content of NPBFs; only 6 studies evaluated the health effects and nutrient content of NPBFs (see Supplementary file 1: Table S9 in the Supporting Information online ).

Reduction of environmental outcomes and their associated nutrient outcomes of novel plant-based foods (NPBFs) compared with baseline (eg, dairy milk and cheese, meat and poultry), expressed in percentage difference . The y -axis shows the increase or decrease of the nutrient content (energy, fiber, sodium, and saturated fat) in comparison with baseline; and the x -axis shows the reduction (or increase) of the environmental categories. Three environmental categories are reported: greenhouse gas emissions (circles), land use (triangles), and blue-water use (squares). Three NPBFs are reported: plant-based (PB) cheese alternatives (brown), PB meat alternatives (purple), and PB drinks (orange). PB yogurts were not included due to the limited amount of data. See Supplementary file 2 in the Supporting Information online for detailed information on the baseline used for each reference. Data were limited to raw products only.

When compared with ABF counterparts, data suggest NPBFs are overwhelmingly associated with smaller environmental footprints. Data on nutritional profiles of NPBF were mixed: nutritional profiles for some NPBF groups were better aligned with healthy diets, but not for others. Clear co-benefits were observed for fiber intake from NPBFs. However, for the other nutrients, the picture was much more mixed due to the variability in content arising from differences in the main primary ingredients and the type of NPBFs.

Fruit, vegetable, legume, and nut content of novel plant-based foods

The percentage of fruit, vegetable, legume, and nut content in each NPBF in the United Kingdom was estimated as a case study ( Figure 5 ). Most NPBFs had at least 1 fruit, vegetable, legume, or nut, ranging from 0.0% to 100.0% of their weight. Overall, median content was low, with a few exceptions. PB meat alternatives had the highest content of vegetables and legumes, and PB cheese alternatives had the lowest content ( Supplementary file 1: Figure S5 and Supplementary file 2: Table S5 in the Supporting Information online ).

Estimated fruit, vegetable, legume, and nut content (%) in each novel plant-based foods product from time-stamped data from UK supermarkets . Panels show (a) plant-based (PB) drink alternatives; (b) PB meat alternatives; (c) PB cheese alternatives; and (d) PB yogurt alternatives.

Assessment of robustness and relevance of the included studies

For results on the assessment of robustness and relevance of the included studies see Supplementary file 1 : Table S12 in the Supporting Information online in section 3.6 .

Sensitivity analysis of funding sources of nutrient composition studies

Almost half of the nutrition studies included (n = 26; 46.4%) were funded by academic funders; 44.6% (n = 25) were fully funded or partially funded by industry; and 10.0% (n = 5) did not state their funding source. NPBF manufacturers were the support for the majority of industry-funded studies (n = 21; 37.5%), followed by the livestock industry (n = 3; 5.4%), and both (n = 1; 1.8%). The sensitivity analysis of the percentage difference for all the nutrients associated with the burden of disease, except total sugar, revealed that studies funded by industry were more likely to find differences than those funded by academia, with the former typically reporting more positive results on lower energy and saturated fat ( Table 5 and see Supplementary file 1: Table S13 in the Supporting Information online for sensitivity analysis on studies partially funded by the industry). However, the direction across all studies was the same: reductions in energy and saturated fat content, and increases in fiber, total sugar, and sodium content.

Sensitivity analysis, based on funding source, of the percentage difference between novel plant-based foods vs animal-based foods in nutrient content and environmental impacts a

The funding source of 6 articles were unknown, so they were excluded from this analysis. The superscript b and c indicate the direction and dimension of the association.

Industry-funded studies show a more positive impact on health and environmental outcomes of their PB products (vs animal sourced foods) as compared with academically funded studies.

Industry-funded studies show a less positive impact on health and environmental outcomes of their PB products (vs animal-sourced foods) as compared with academically funded studies.

Abbreviations : ABF, animal-based food; IQR, interquartile range; NPBF, novel plant-based food.

Sensitivity analysis of funding sources of health studies

Only 2 health studies were funded by academia; the rest of the studies were either partially or wholly funded by industry (n = 9). Most industry-funded studies were from NPBF manufacturers (n = 8); 1 study was partially funded by Dairy Australia.

Sensitivity analysis of funding sources of environmental studies

Compared with nutritional studies, a greater percentage of environmental studies were by industry researchers, particularly from NPBF manufacturers (67.9%). Approximately 71.7% of studies (n = 38) were fully funded or partially funded by industry; 26.4% (n = 14) were supported by academic funders; and 1.9% (n = 1) did not state their funding source. Of the industry-funded studies, only 2 (3.8%) were funded by the livestock industry. The sensitivity analysis revealed that the percentage differences were significantly larger between academic and industry funders in terms of GHGE and LU. Studies funded by industry typically reported more positive results on LU than did studies funded by academic funders, and the opposite was observed for GHGE. Like nutrient studies, the direction (decreases in GHGE, LU, and WF) was the same regardless of the funding source ( Table 5 , and see Supplementary file 1: Table S13 in the Supporting Information online for the sensitivity analysis of studies partially funded by the industry).

Research findings

We reviewed evidence from high-income countries that was published in peer-reviewed and grey literature within the past 7 years on nutrient content, and environmental and health outcomes of consuming NPBFs. Most NPBFs typically have much lower environmental impacts compared with ABFs, particularly with respect to GHGE and, to a lesser extent, to LU and WF. The nutrient content of NPBFs is highly variable in comparison to the nutrient profiles of ABFs. Although several individual NPBFs had positive health and environmental outcomes, co-benefits identified were not universal across all NPBFs and several trade-offs were identified. The main primary ingredient, type of product, processing techniques, and brand were all important determinants of health, and nutritional and environmental outcomes, findings that show the need for further subcategorization of NPBFs to better educate consumers and enable them to take informed decisions regarding the healthiness and sustainability of their diets and (potential) dietary changes.

Research in context

If carefully selected, certain NPBFs (particularly certain PB drinks and meat alternatives) could be an effective part of interventions to achieve net-zero and health targets in high-income countries. By applying a combination of strategies, enhanced uptake of these foods could improve the nutritional quality of diets, improve health, and contribute to tackling climate change impacts.

At the macronutrient level, NPBFs are generally the healthier option, given their higher fiber content and typically lower saturated fat and calorie contents, which could be advantageous in high-income (often obesogenic) settings. Certain types of NPBFs, particularly mycoprotein and legume-based meats, often also contain a substantial amount of fruit, vegetables, legumes, and/or nuts, which are food groups that are typically underconsumed in high-income settings. Composition of legume and fruit and vegetable-based drinks, were also typically consistent with healthier diets in high-income food secure settings, including low energy density, low total sugar, high fiber and low saturated fat content. Caution is recommended in the selection of these products if they were to be part of dietary recommendations, or standard institutional procurement for example, as certain NPBFs can also have higher levels of total sugar, sodium, and saturated fats in comparison to their respective ABF. This is particularly true for certain cereal and grain-based drinks, and coconut-based cheese and yogurts. Although the specific type of oil used in each NPBF product was not analyzed, coconut oil, which is high in saturated fatty acids, is often the ingredient that increases saturated fat levels in NPBFs to levels similar to its ABF counterparts. 51 , 75 Indeed, coconut oil-based cheese had approximately 50% more saturated fat than dairy cheese, and typically contained the least amount of fruit, vegetables, legumes or nuts, with the majority being absent.

In line with other evidence, 39 , 97 , 98 fortified NPBFs, in some cases, can be nutritionally comparable to their respective ABFs. Some individual NPBFs contained even higher concentrations of iron, vitamin B 12 , and calcium, whereas others did not. However, micronutrient assessment was difficult because not all included studies reported micronutrients. This could be because either NPBFs were unfortified or the information simply was not reported. Especially when nutrient information is gathered from supermarket websites for individual studies, micronutrient data are generally not reported.

The highly varying nutrient content across and within all PB products and categories may cause consumer confusion when individuals are looking for healthy and environmentally friendly alternatives to ABFs. Clearer front-of-package labelling of certain nutrients and information campaigns could reduce such confusion and better enable the consumer to make informed decisions about food purchases. 99 Potential development of rules and regulations on the food standards of NPBFs could also be a step forward in having a larger range of “healthy” NPBFs, because such regulations could potentially encourage reformulation of NPBFs, including the reduction of sodium, total sugar, and saturated fat content, and increased micronutrients. From a technological perspective, this is certainly possible. For example, new biotechnological techniques have been developed that enable companies to reduce sugar content and improve palatability, nutrient profile, and digestibility of PB drinks. 67 , 100–103 Some processing techniques can also decrease levels of anti-nutrients and polyphenols, which commonly are associated with low mineral and vitamin bioavailability, 35 , 98 , 101 , 104–107 and increase protein yield. 101 Given that specific raw materials, isolated proteins, processing levels, and fortification methods, often used in NPBFs, as compared with ABF nutrient profiles, are still debated in the scientific community, further research on the nutrient content and health risks related to bioavailability, bioaccessibility, and byproduct formation during industrial processes will reveal whether there are differences in terms of health impacts of “natural” vs more “isolated” nutrients. 30 , 108 , 109 More research into the metabolic profiles of NPBFs is imperative, particularly in light of a recent study identifying differences in the abundance of profiled metabolites between beef and PB burgers, despite their labelled nutritional similarities. 110 Instead of continuing the debate between the superiority of ABFs vs NPBFs, or vice versa, acknowledging and embracing their complementary differences can contribute to a less polarized dietary transition. This is especially relevant because emerging evidence has suggested that people who consume NPBFs also tend to purchase ABFs. 111

From the limited evidence on health, the inclusion of NPBFs into diets appears to typically have beneficial health effects, particularly the consumption of PB meat alternatives. The positive health effects mostly relate to better weight management and associated reduced risk of noncommunicable diseases in high-income (and often obesogenic) countries. This is aligned with a recently published meta-analysis that found positive outcomes on total cholesterol, low-density lipoprotein cholesterol and triglycerides when consuming PB meat alternatives as replacements for meat. 51 Furthermore, a few older studies also found positive health outcomes when assessing consumption of mycoprotein-based foods (eg, drinks, cookies, milkshakes, crisps) 112–115 and soy protein with isoflavones, 50 compared with consumption of dairy milk and/or meat products.

Previous evidence revealed that NPBFs are often regarded as healthier alternatives to ABFs 116 ; hence, it could be hypothesized that people may consume NPBFs in larger quantities than they would otherwise have done when eating ABFs. This may have negative health implications, especially if consumed regularly. Establishing a clear division in PB foods classifications, including ultraprocessed and less processed PB alternative foods, could enable better assessment of short- and long-term health impacts of NPBFs if they were to be consumed at an even larger scale. 116

Ultraprocessed foods have been associated with many diet-related diseases because these foods are generally energy dense and hyperpalatable. 117 , 118 Almost all NPBFs fall, technically, within this category; however, in this review, we found that the nutritional composition of some NPBFs aligns well with healthy dietary recommendations, such as having a high fiber content, low energy density, and low saturated fat content. Additionally, 1 of the included studies 90 also found positive associations with the gut microbiome when substituting meat in certain meals with PB meat alternatives. To get a better overview of the overall effect of NPBFs on health, more information and detailed analyses are needed regarding level of processing and gastrointestinal fate.

Consistent evidence was found regarding environmental outcomes, similar to previous research. 52 , 53 , 108 , 119–121 Most NPBFs had smaller environmental footprints than their ABF counterparts, with median reductions reported of up to 94.3%, 89.5%, and 92.6% for GHGE, LU, and WF, respectively. Nevertheless, some PB products had greater environmental impacts than their ABF counterparts, with some extreme outliers particularly in terms of WF. Although evidence was rather consistent, and the direction of effect appears to be clear, care should be taken not to overinterpret the exact numerical results: environmental impact calculations are notoriously context dependent and sensitive to methodological and data choices. This makes it impossible to come up with a summary figure that is representative for all products, produced in all countries; generally, however, there is a broad body of evidence demonstrating a reduction in GHGE, LU, and WF for a wide range of PB products in a wide variety of contexts compared with their ABF equivalents.

To improve the strategic use of NPBFs to achieve more sustainable food systems, life cycle assessments of these products should incorporate the full range of environmental impact categories, as well as sociocultural, economic, and health impacts with harmonized methods and assumptions across studies.

This study revealed an evidence gap for health impacts of NPBFs, including mental and dental health, and other risks associated with micronutrient deficiencies. There is also a lack of health studies on PB yogurts, PB cheese, and PB egg alternatives. Research on the health effects of PB drinks has been conducted with only certain products, “generally soy and almond drinks,” but there is a gap in knowledge about other PB drinks, such as those made from oat, potato, and hazelnut, among others. Furthermore, some concerns have been raised about the carbohydrate content in some PB drinks. A study by Jeske et al 122 revealed that the presence of β-glucan in many oat-based drinks causes a moderate glycemic index, despite the high carbohydrate content. In fact, Dhankhar 104 associated the consumption of oat drinks with high β-glucan levels with a reduction in cholesterol levels in study participants. However, this evidence needs to be updated to reflect the potential benefits of different types of PB drinks and current market brands. Although dairy products contain naturally occurring sugars from lactose, it is difficult to determine the breakdown of “natural” vs added sugars in NPBFs from the available literature. More research is also required on dental health to assess the potential risks of increased dental cavities due to lower calcium bioavailability, and the effects of free sugar content, pH levels, and buffering capacity in NPBFs.

Additional research is needed to provide more nutrient environmental and health evidence for PB yogurts, cheese, and egg alternatives. Last, although this review assessment focused on 3 environmental outcomes, evidence on other environmental impacts, including biodiversity loss and socioeconomic implications, is scarce. Across the 3 themes assessed in this review, better standardization and clear reporting of results in NPBF studies in the future would facilitate updates of this review.

Relevance for policy and practice

Minimally processed PB foods are still considered the gold standard for healthier and more sustainable diets. However, shifts from ABFs to PB whole foods remain problematic because, despite all the scientific knowledge about healthy eating, dietary change toward minimally processed PB foods has not been achieved. This review revealed that NPBFs can be healthier and more environmentally friendly alternatives to ABF consumption, if carefully selected. Although behavioral aspects are embedded in this transition, NPBFs could offer a convenient, novel, and potentially more realistic option to facilitate dietary transitions at large scale, diversifying diets, and increasing consumption of fruits, vegetables, legumes, and nuts without the need for significant individual dietary habits.

For potential promotion of the inclusion of NPBFs as part of public procurement or embedding them into food-based dietary guidelines, some of the consideration regarding varying healthiness of specific types of NPBFs and the need for further subclassifications needs to be carefully addressed. Furthermore, affordability is a concern because NPBFs often are more expensive than their ABF counterparts. Although comprehensively synthesizing price data was outside of the scope of this study, in the United Kingdom, the Food Foundation found that PB drinks are, on average, 50.0% more expensive than dairy milk. 71

Active promotion of NPBFs would require more detailed analysis of consumer behavior: current consumption of NPBFs is generally higher among younger generations, women, White populations, and those with higher education and incomes. 28 Better understanding of main drivers and barriers of consumption of NPBFs would allow targeted promotion to widen this consumer group. 71 NPBFs could play an additional role in reducing the prevalence of micronutrient deficiencies, especially given their reformulation and fortification potential. For example, in Finland, a mass fortification strategy of vitamin D across dairy and nondairy products has shown positive health outcomes over the past decade. 123 Finally, formalization, standardization, and accountability of environmental labelling could help consumers making informed decisions and avoid misinformation.

Strengths and limitations

To our knowledge, this is the first systematic review assessing the published peer-reviewed and grey literature evidence from studies that evaluated nutrient, and health and environmental impacts or benefits of NPBFs. A strict and comprehensive search string was developed to assess the full breadth of studies and reports, and machine-learning models were used to filter the large number of studies and systematically present all the available evidence on various NPBFs.

This study only covered the past 7 years to assess the current evidence, and an exhaustive cross-check of references was not performed, which possibly introduces reporting bias for missed relevant studies from previous years. However, it was assumed that only a small amount of additional findings had been missed, given the recent emergence of the variety and types of these novel products. Second, only 3 environmental impact categories were examined: carbon footprint, LU, and blue-water consumption. However, the heterogeneity of study designs, from system boundaries to geographical location, agricultural inputs, and methods used to calculate environmental footprints, made the review process too time consuming to expand on other environmental impacts in this particular study. Reliable reporting of environmental impacts of novel ingredients used in NPBFs, including added minerals and vitamins for fortification purposes, are generally missing in many studies. All the data reported by authors were collected and each study was compared individually against its own baseline (ie, the ABF comparator provided by author). Given the large spectrum of methods to determine environmental footprints, this could have introduced some bias; however, the alternative (using a standardized comparator) would equally have its limitations (eg, this would not be representative for all farming systems and products). Third, products and nutrients were assessed individually. Although the nutrient content gives some guidance on probable health risks, in reality, people consume diets in which individual compounds interact, influencing unknown biological pathways. Fourth, several studies that did not specifically report on the proportion and type of NPBF in (self-)reported PB diets had to be excluded. For those studies, it was impossible, therefore, to assess the effect on health and environment of NBPFs alone vs all PB foods together (ie, whole foods, NPBFs, other PB foods such as tofu and tempeh) and complicated any efforts to calculate dietary shifts. Finally, most studies did not report the precision of measures of effect (n = 68), making it difficult to pool and synthesize results across the 3 themes assessed in this review.

Food systems and diets need to change to meet environmental and health targets. This comprehensive systematic review presents a holistic approach to summarize the evidence on the nutrient, health, and environmental impacts of NPBF consumption. Although PB whole foods remain the preferred option on health grounds, some NPBFs have potential for being a useful steppingstone in the process of food system and dietary transformation, functioning as a healthy and environmentally friendly alternative to ABFs, if carefully selected. Reformulation and fortification could further enhance NPBFs as a viable and effective food group that could accelerate the dietary transition toward sustainable and healthy diets. However, given the great variability in nutritional composition of individual NPBFs, widespread promotion of such products should be introduced and addressed with caution. Given that NPBFs are already important in the food system and consumption is expected to continue to increase, a few steps are urgently required to guide consumers and enable them to make informed decisions regarding their diets. These include a further subdivision or categorization of NPBFs, which currently fall mainly in the ultraprocessed (hence, “unhealthy”) food category. Furthermore, standardized and verifiable environmental assessments of NPBFs are needed to compare foods with regard to their environmental footprints. Finally, more research on the short- and longer-term health effects of NPBFs is urgently required to facilitate informed decision-making on the inclusion of NPBFs as part of a wider net-zero and health strategy.

Gratitude is extended to the authors who responded to inquiries and generously shared their individual data. Additionally, sincere appreciation is expressed to the FoodDB team for sharing their time-stamped data set of observations from UK supermarkets to estimate the total fruit, vegetable, legume, and nut content of foods.

Author contributions. S.N.E. contributed to conceptualization of the study, methodology, investigation, data curation, formal analysis, coding and analysis of machine learning, and writing the original draft of the article. G.H. contributed to the formal analysis (screening process), data validation, and review and editing of the manuscript. A.J.S. led the coding and analysis of machine learning, and reviewed and edited the manuscript. C.A.-C. and G.T. contributed to the literature screening process, and reviewed and edited the manuscript. R.G. reviewed and edited the manuscript. S.P. and R.P. contributed to data validation, and reviewed and edited the manuscript. P.S. contributed to conceptualization of the study, methodology, reviewed and edited the manuscript, supervised the work, acquired funding, and contributed to project administration.

Funding. This work was supported by a research grant from the National Institute for Health Research, Health Protection Research Unit PhD Studentship in Environmental Change and Health (grant NIHR200909) and the af Jochnick Foundation.

The funders had no role in the conception, design, performance, and approval of this work.

Declaration of interest. The authors have no relevant interests to declare.

Data availability. Source code for this work is available online (DOI: 10.5281/zenodo.7116157).

The following supporting information is available through the online version of this article at the publisher’s website:

Supplementary file 1 .

Supplementary file 2 .

Supplementary file 3 .

Box 1 Key Definitions

Novel plant-based foods (NPBFs): Acknowledging differences in terminology for NPBFs, for the purpose of this review, the term novel plant-based foods is used to describe plant-based (PB) drinks and PB meat, cheese, eggs, and yogurt alternatives that are of plant or fungal origin and designed to directly replace or mimic animal-based foods. This definition includes fungi-based foods (ie, mycoprotein) that biologically do not belong to the plant kingdom but are typically “designed” similarly to NPBFs as a direct replacement for animal-based foods. Here, the term excludes tofu, tempeh, and seitan because although these might be novel to some high-income settings, they have been part of traditional Asian diets for centuries and, hence, are not subject to the same challenges and evidence gap as NPBFs.

Ultraprocessed: Foods that have undergone a series of industrial techniques and processes

Minimally processed plant-based foods: Plant-based whole foods such as nuts, seeds, cereals, and legumes

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• 2 Department of Pathology, Guiqian International General Hospital, Guiyang, China

Introduction: Malignant peritoneal mesothelioma (MPM) is an extremely rare tumor with nonspecific clinical manifestations, making diagnosis challenging.

Case presentation: Herein, we report a case of MPM with occult onset presenting with bilateral hydronephrosis and renal insufficiency. A 30-year-old man was admitted to the Urology Department because of recurrent bilateral lower back pain. The etiology was unclear after a series of laboratory tests, imaging examinations, bone marrow aspiration, renal puncture biopsy, ascites examination, ureteroscopy, and so on. Finally, MPM was diagnosed by laparoscopic exploration and biopsy. Moreover, during the course of the disease, the patient's bilateral ureters were compressed, and the obstruction could not be relieved after the placement of ordinary ureteral stents. Percutaneous nephrostomy or metal ureteral stenosis was appropriate in managing malignant ureteral obstruction as it could improve renal function.

Conclusions: The onset of this case was insidious, and the diagnosis was difficult, with a poor prognosis. To date, only a handful of cases have been reported. We hope this case can provide some enlightenment for our clinical work.

Introduction

Malignant peritoneal mesothelioma (MPM) is an aggressive neoplasm that can rapidly spread within the abdominal area. Patients with peritoneal mesothelioma usually present with an abdominal mass, ascites, and abdominal pain. Herein, we report a case with bilateral hydronephrosis and renal insufficiency as the first symptoms. The case was extremely challenging to diagnose, which was finally confirmed based on laparoscopic exploration and biopsy. This study aimed to provide clinical evidence for the diagnosis, treatment, and prognosis of rare MPM.

Case presentation

A 30-year-old man was admitted to the Urology Department because of repeated bilateral lower back pain for 3 months. At the onset of the illness, computed tomography (CT) scans revealed bilateral hydronephrosis, and the serum creatinine (SCr) level was 123 μmol/L. Symptoms improved after the placement of bilateral ureteral stents. However, the back pain recurred 1 month later, accompanied by abdominal distension, nausea, and vomiting. Enhanced CT scans revealed bilateral hydronephrosis, splenomegaly, and ascites. Hydronephrosis had aggravated, with SCr levels increasing to 305 µmol/L. A transurethral cystoscopy revealed no lower urinary tract obstruction. Ureteroscopy indicated narrowing of the lower part of the bilateral ureter, approximately 6 cm from the ureteral opening. During hospitalization, the patient's condition continued to deteriorate, with a progressive decrease in urine volume. The highest SCr level was 470 μmol/L. A plain CT scan revealed bilateral hydronephrosis, splenomegaly, abdominal effusion, peritoneal thickening with exudative changes, and intestinal wall thickening, with no significant mass observed. We performed a bilateral percutaneous nephrostomy (PCN) and abdominal catheterization. Ascites analysis revealed no definite malignant cells. Serum IgG4 level testing yielded negative results. A renal needle biopsy indicated moderate to severe chronic tubulointerstitial injury. Finally, laparoscopic exploration was performed, and intraoperative findings revealed numerous small, shiny, whitish nodules carpeting all visualized peritoneal surfaces and some parts of the intestinal tubes. The tumor infiltrated the entire omentum, forming a large, firm mass ( Figure 1 ). A biopsy of the omentum itself confirmed the diagnosis of peritoneal mesothelioma. Histological findings revealed fibrous tissue hyperplasia with inflammatory cell infiltration and papillary hyperplasia of the overlying mesothelium. The immunohistochemical (IHC) markers were as follows: calretinin (+), CK (+), desmin (-), HMB45 (-), Ki-67 (10%+), CD34 (-), MC (HBME-1) (+), melan-A (-), and B-catenin (+) ( Figure 2 ).

Figure 1 . ( A ) Numerous small nodules carpeting all visualized peritoneal and some parts of intestinal tube surfaces. ( B ) Tumor infiltrating the entire omentum and forming a large, firm mass.

Figure 2 . Histology and immunohistochemistry of the omentum. ( A , B ) Mass of cells lined with a papillary structure of monolayer flat/cuboidal mesothelial cells with a milder nucleus and acidophilic cytoplasm (H&E, ×100). ( C , D ) Immunohistochemistry results for calretinin and MC (HBME-1) (×100).

Unfortunately, the patient refused to undergo therapy and chose to be discharged for recuperation. During the follow-up, he died at home 1 month after discharge.

Discussion and conclusions

Malignant peritoneal mesothelioma is an aggressive neoplasm of the serosal membranes, first reported by Miller and Wynn in 1908 ( 1 ). It accounts for approximately 25% of malignant mesotheliomas. Asbestos exposure is a well-recognized high-risk pathogenic factor for MPM ( 2 ). The patient was a deaf–mute construction worker with no clear history of asbestos exposure. Patients with peritoneal mesothelioma usually present with abdominal pain, distention, ascites, and an abdominal mass. Hydronephrosis rarely occurs as the first symptom. We searched PubMed for articles addressing peritoneal mesothelioma and hydronephrosis and found five relevant articles, screened by title and abstract. Two articles were finally included in the review. Detailed case data of four patients were obtained ( Table 1 ).

Table 1 . Characteristics of four cases of peritoneal mesothelioma presenting with hydronephrosis, as screened from PubMed and our patient.

Among these cases, the majority had a survival period of only a few months after the first diagnosis. Four out of five presented with combined bilateral hydronephrosis. Ureteral stenting was initially used in the majority of patients to drain hydronephrosis. Renal function improvement was observed in two patients. Therefore, the drainage mode should be considered when dealing with ureteral obstruction. There is no consensus on the optimal method for malignant ureteral obstruction (MUO). Some studies ( 5 ) showed that the postoperative stent failure rate of extrinsic malignant ureteral obstruction was 42%–45%. However, there was no difference in median survival compared with PCN. Metallic stents and some new material stents provide more options. The type and level of obstruction, renal insufficiency, degree of hydroneurosis, and length of obstruction >3 cm have been identified as predictors of stent failure in MUO patients. Accordingly, all these aspects should be taken into consideration. Clinician preference and patient comfort are also important factors.

Diagnosing MPM is extremely challenging, as it is characterized by irregular or nodular peritoneal or mesenteric thickening, omental mass, and ascites in imaging evaluations. The accuracy of ascitic cytology is only 50% ( 6 ). Laparoscopy is superior to CT in the evaluation of localized peritoneal metastases. The gold standard for MPM diagnosis is pathological examination. Morphologically, there are mainly three subtypes of MPM: epithelioid, sarcomatoid, and biphasic. Epithelioid MPM is the most common and least aggressive subtype, accounting for approximately 60% of cases. Our patient belongs to the epithelioid type, as evidenced by the histological findings showing papillary hyperplasia of the overlying mesothelium. However, the diffused growth pattern of the tumor and the limited tissue obtained by laparoscopic biopsy present challenges for pathological examination. In combination with the prognosis of the patient, it can be mixed with a few sarcomatoid types. IHC staining is the most valuable and feasible method for the differential diagnosis of MPM ( 7 ). The recognized positive markers are calretinin, CK 5/6, WT-1, HBME-1, thrombomodulin, podoplanin, mesothelin, and D2-40, while the negative markers are TTF1, carcinoembryonic antigen (CEA), Ber Ep4, B72.3, MOC31, and CD15. It is recommended to use at least two positive and two negative markers for differential diagnosis ( 8 ).

In 2011, Yan et al. ( 9 ) proposed a TNM staging system based on the extent of peritoneal disease burden (T), intra-abdominal nodal metastasis (N), and extra-abdominal metastasis (M) to standardize and guide the clinical treatment and prognostic evaluation of MPM. The T stage is determined by calculating the peritoneal carcinomatosis index (PCI). This assessment combines lesion size (0–3) with tumor distribution (abdominopelvic and mesenteric regions 0–13) to quantify the extent of disease as a numerical score (PCI-0 to 39). The 5-year survival rates of stage I, II, and III patients were reported to be 87%, 53%, and 29%, respectively. The patient’s PCI was >30, categorizing MPM as stage III (T4). This staging was an independent prognostic factor for malignant peritoneal mesothelioma.

Cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is the initial preferred treatment for MPM. An analysis by the US HIPEC Collaborative, including 130 patients with MPM (all histologic subtypes included) who underwent CRS-HIPEC, reported a 5-year OS of 67.8% and a conditional OS of 89.7%. The strongest predictor of long-term survival is complete cytoreduction ( 10 ). Our patient presented with diffuse MPM, with extensive peritoneal, small bowel serosal, or mesentery involvement, which is not amenable to complete cytoreduction. The proposed treatment plan is intravenous chemotherapy and HIPEC, and immunosuppressive therapy can be added if physical conditions allow. The current preferred intraperitoneal chemotherapy is cisplatin alone or in combination with cisplatin/doxorubicin, the most commonly used combination therapy. Systemic therapy is an alternative treatment for inoperable patients. The International Expanded Access Program assessed pemetrexed regimens for 109 patients with MPM. Patients received pemetrexed, pemetrexed plus cisplatin, or pemetrexed plus carboplatin as either first-line or second-line therapy. For patients who received pemetrexed plus cisplatin, the 1-year survival rate was 57.4%. For patients who received pemetrexed alone, the median survival rate was 10.3 months, and the 1-year survival rate was 41.5%. Survival rates are not available for pemetrexed plus carboplatin ( 11 ). In recent years, molecular therapy and immunotherapy have attracted increasing attention. BAP1, TP53, NF2, and ALK, which are commonly mutated genes in MPM ( 12 ), are expected to become potential therapeutic targets. A phase II study evaluated the activity of pembrolizumab in 64 mesothelioma patients who had been treated with one or two chemotherapy regimens. Among these patients, only eight (12.5%) had MPM, and they exhibited lower overall response rates than patients with pleural mesothelioma in the study. Whether PDL1 expression is predictive of benefit remains unknown. In another cohort study evaluating the clinical efficacy of immunotherapy in patients with advanced MPM, the overall response rate was 19%, with a reported median progression-free survival (PFS) of 5.5 months ( 13 ) . Immunotherapy is an exciting future direction for MPM, and we look forward to the results of more clinical trials.

Peritoneal mesothelioma with bilateral hydronephrosis as the first symptom is rare and the diagnosis can be confirmed by laparoscopic exploration biopsy when necessary. Because of severe ureteral compression, PCN, or metal stents with high tension, offer more advantages than ordinary stents in improving renal function.

Data availability statement

The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.

Ethics statement

This study involving humans was approved by the ethics committee of the Guiqian International General Hospital. The studies were conducted in accordance with local legislation and institutional requirements. The participants provided their written informed consent to participate in this study. Written informed consent was obtained from the participant/patient(s) for the publication of this case report.

Author contributions

JL: Conceptualization, Data curation, Validation, Writing – original draft, Writing – review & editing. JP: Resources, Writing – review & editing. CZ: Investigation, Software, Validation, Writing – review & editing. LW: Formal analysis, Validation, Writing – review & editing. HZ: Conceptualization, Funding acquisition, Methodology, Project administration, Writing – review & editing.

The authors declare that no financial support was received for the research, authorship, and/or publication of this article.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's note

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Supplementary material

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fsurg.2024.1342657/full#supplementary-material

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Keywords: peritoneal mesothelioma, hydronephrosis, percutaneous nephrostomy, ureteral stent, case report

Citation: Luo J, Pan J, Zhong C, Wang L and Zhang H (2024) Malignant peritoneal mesothelioma presenting with bilateral hydronephrosis and renal insufficiency: a case report and literature review. Front. Surg. 11:1342657. doi: 10.3389/fsurg.2024.1342657

Received: 22 November 2023; Accepted: 3 April 2024; Published: 24 April 2024.

Reviewed by:

© 2024 Luo, Pan, Zhong, Wang and Zhang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Heng Zhang [email protected]