how do you critically review a research paper

How to Write Critical Reviews

When you are asked to write a critical review of a book or article, you will need to identify, summarize, and evaluate the ideas and information the author has presented. In other words, you will be examining another person’s thoughts on a topic from your point of view.

Your stand must go beyond your “gut reaction” to the work and be based on your knowledge (readings, lecture, experience) of the topic as well as on factors such as criteria stated in your assignment or discussed by you and your instructor.

Make your stand clear at the beginning of your review, in your evaluations of specific parts, and in your concluding commentary.

Remember that your goal should be to make a few key points about the book or article, not to discuss everything the author writes.

Understanding the Assignment

To write a good critical review, you will have to engage in the mental processes of analyzing (taking apart) the work–deciding what its major components are and determining how these parts (i.e., paragraphs, sections, or chapters) contribute to the work as a whole.

Analyzing the work will help you focus on how and why the author makes certain points and prevent you from merely summarizing what the author says. Assuming the role of an analytical reader will also help you to determine whether or not the author fulfills the stated purpose of the book or article and enhances your understanding or knowledge of a particular topic.

Be sure to read your assignment thoroughly before you read the article or book. Your instructor may have included specific guidelines for you to follow. Keeping these guidelines in mind as you read the article or book can really help you write your paper!

Also, note where the work connects with what you’ve studied in the course. You can make the most efficient use of your reading and notetaking time if you are an active reader; that is, keep relevant questions in mind and jot down page numbers as well as your responses to ideas that appear to be significant as you read.

Please note: The length of your introduction and overview, the number of points you choose to review, and the length of your conclusion should be proportionate to the page limit stated in your assignment and should reflect the complexity of the material being reviewed as well as the expectations of your reader.

Write the introduction

Below are a few guidelines to help you write the introduction to your critical review.

Introduce your review appropriately

Begin your review with an introduction appropriate to your assignment.

If your assignment asks you to review only one book and not to use outside sources, your introduction will focus on identifying the author, the title, the main topic or issue presented in the book, and the author’s purpose in writing the book.

If your assignment asks you to review the book as it relates to issues or themes discussed in the course, or to review two or more books on the same topic, your introduction must also encompass those expectations.

Explain relationships

For example, before you can review two books on a topic, you must explain to your reader in your introduction how they are related to one another.

Within this shared context (or under this “umbrella”) you can then review comparable aspects of both books, pointing out where the authors agree and differ.

In other words, the more complicated your assignment is, the more your introduction must accomplish.

Finally, the introduction to a book review is always the place for you to establish your position as the reviewer (your thesis about the author’s thesis).

As you write, consider the following questions:

• Is the book a memoir, a treatise, a collection of facts, an extended argument, etc.? Is the article a documentary, a write-up of primary research, a position paper, etc.?
• Who is the author? What does the preface or foreword tell you about the author’s purpose, background, and credentials? What is the author’s approach to the topic (as a journalist? a historian? a researcher?)?
• What is the main topic or problem addressed? How does the work relate to a discipline, to a profession, to a particular audience, or to other works on the topic?
• What is your critical evaluation of the work (your thesis)? Why have you taken that position? What criteria are you basing your position on?

Provide an overview

In your introduction, you will also want to provide an overview. An overview supplies your reader with certain general information not appropriate for including in the introduction but necessary to understanding the body of the review.

Generally, an overview describes your book’s division into chapters, sections, or points of discussion. An overview may also include background information about the topic, about your stand, or about the criteria you will use for evaluation.

The overview and the introduction work together to provide a comprehensive beginning for (a “springboard” into) your review.

• What are the author’s basic premises? What issues are raised, or what themes emerge? What situation (i.e., racism on college campuses) provides a basis for the author’s assertions?
• How informed is my reader? What background information is relevant to the entire book and should be placed here rather than in a body paragraph?

Write the body

The body is the center of your paper, where you draw out your main arguments. Below are some guidelines to help you write it.

Organize using a logical plan

Organize the body of your review according to a logical plan. Here are two options:

• First, summarize, in a series of paragraphs, those major points from the book that you plan to discuss; incorporating each major point into a topic sentence for a paragraph is an effective organizational strategy. Second, discuss and evaluate these points in a following group of paragraphs. (There are two dangers lurking in this pattern–you may allot too many paragraphs to summary and too few to evaluation, or you may re-summarize too many points from the book in your evaluation section.)
• Alternatively, you can summarize and evaluate the major points you have chosen from the book in a point-by-point schema. That means you will discuss and evaluate point one within the same paragraph (or in several if the point is significant and warrants extended discussion) before you summarize and evaluate point two, point three, etc., moving in a logical sequence from point to point to point. Here again, it is effective to use the topic sentence of each paragraph to identify the point from the book that you plan to summarize or evaluate.

Questions to keep in mind as you write

With either organizational pattern, consider the following questions:

• What are the author’s most important points? How do these relate to one another? (Make relationships clear by using transitions: “In contrast,” an equally strong argument,” “moreover,” “a final conclusion,” etc.).
• What types of evidence or information does the author present to support his or her points? Is this evidence convincing, controversial, factual, one-sided, etc.? (Consider the use of primary historical material, case studies, narratives, recent scientific findings, statistics.)
• Where does the author do a good job of conveying factual material as well as personal perspective? Where does the author fail to do so? If solutions to a problem are offered, are they believable, misguided, or promising?
• Which parts of the work (particular arguments, descriptions, chapters, etc.) are most effective and which parts are least effective? Why?
• Where (if at all) does the author convey personal prejudice, support illogical relationships, or present evidence out of its appropriate context?

Keep your opinions distinct and cite your sources

Remember, as you discuss the author’s major points, be sure to distinguish consistently between the author’s opinions and your own.

Keep the summary portions of your discussion concise, remembering that your task as a reviewer is to re-see the author’s work, not to re-tell it.

And, importantly, if you refer to ideas from other books and articles or from lecture and course materials, always document your sources, or else you might wander into the realm of plagiarism.

Include only that material which has relevance for your review and use direct quotations sparingly. The Writing Center has other handouts to help you paraphrase text and introduce quotations.

Write the conclusion

You will want to use the conclusion to state your overall critical evaluation.

You have already discussed the major points the author makes, examined how the author supports arguments, and evaluated the quality or effectiveness of specific aspects of the book or article.

Now you must make an evaluation of the work as a whole, determining such things as whether or not the author achieves the stated or implied purpose and if the work makes a significant contribution to an existing body of knowledge.

Consider the following questions:

• Is the work appropriately subjective or objective according to the author’s purpose?
• How well does the work maintain its stated or implied focus? Does the author present extraneous material? Does the author exclude or ignore relevant information?
• How well has the author achieved the overall purpose of the book or article? What contribution does the work make to an existing body of knowledge or to a specific group of readers? Can you justify the use of this work in a particular course?
• What is the most important final comment you wish to make about the book or article? Do you have any suggestions for the direction of future research in the area? What has reading this work done for you or demonstrated to you?

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Ten Simple Rules for Writing a Literature Review

Marco pautasso.

• Author information
• Article notes
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* E-mail: [email protected]

The author has declared that no competing interests exist.

Collection date 2013 Jul.

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

Literature reviews are in great demand in most scientific fields. Their need stems from the ever-increasing output of scientific publications [1] . For example, compared to 1991, in 2008 three, eight, and forty times more papers were indexed in Web of Science on malaria, obesity, and biodiversity, respectively [2] . Given such mountains of papers, scientists cannot be expected to examine in detail every single new paper relevant to their interests [3] . Thus, it is both advantageous and necessary to rely on regular summaries of the recent literature. Although recognition for scientists mainly comes from primary research, timely literature reviews can lead to new synthetic insights and are often widely read [4] . For such summaries to be useful, however, they need to be compiled in a professional way [5] .

When starting from scratch, reviewing the literature can require a titanic amount of work. That is why researchers who have spent their career working on a certain research issue are in a perfect position to review that literature. Some graduate schools are now offering courses in reviewing the literature, given that most research students start their project by producing an overview of what has already been done on their research issue [6] . However, it is likely that most scientists have not thought in detail about how to approach and carry out a literature review.

Reviewing the literature requires the ability to juggle multiple tasks, from finding and evaluating relevant material to synthesising information from various sources, from critical thinking to paraphrasing, evaluating, and citation skills [7] . In this contribution, I share ten simple rules I learned working on about 25 literature reviews as a PhD and postdoctoral student. Ideas and insights also come from discussions with coauthors and colleagues, as well as feedback from reviewers and editors.

Rule 1: Define a Topic and Audience

How to choose which topic to review? There are so many issues in contemporary science that you could spend a lifetime of attending conferences and reading the literature just pondering what to review. On the one hand, if you take several years to choose, several other people may have had the same idea in the meantime. On the other hand, only a well-considered topic is likely to lead to a brilliant literature review [8] . The topic must at least be:

interesting to you (ideally, you should have come across a series of recent papers related to your line of work that call for a critical summary),

an important aspect of the field (so that many readers will be interested in the review and there will be enough material to write it), and

a well-defined issue (otherwise you could potentially include thousands of publications, which would make the review unhelpful).

Ideas for potential reviews may come from papers providing lists of key research questions to be answered [9] , but also from serendipitous moments during desultory reading and discussions. In addition to choosing your topic, you should also select a target audience. In many cases, the topic (e.g., web services in computational biology) will automatically define an audience (e.g., computational biologists), but that same topic may also be of interest to neighbouring fields (e.g., computer science, biology, etc.).

Rule 2: Search and Re-search the Literature

After having chosen your topic and audience, start by checking the literature and downloading relevant papers. Five pieces of advice here:

keep track of the search items you use (so that your search can be replicated [10] ),

keep a list of papers whose pdfs you cannot access immediately (so as to retrieve them later with alternative strategies),

use a paper management system (e.g., Mendeley, Papers, Qiqqa, Sente),

define early in the process some criteria for exclusion of irrelevant papers (these criteria can then be described in the review to help define its scope), and

do not just look for research papers in the area you wish to review, but also seek previous reviews.

The chances are high that someone will already have published a literature review ( Figure 1 ), if not exactly on the issue you are planning to tackle, at least on a related topic. If there are already a few or several reviews of the literature on your issue, my advice is not to give up, but to carry on with your own literature review,

Figure 1. A conceptual diagram of the need for different types of literature reviews depending on the amount of published research papers and literature reviews.

The bottom-right situation (many literature reviews but few research papers) is not just a theoretical situation; it applies, for example, to the study of the impacts of climate change on plant diseases, where there appear to be more literature reviews than research studies [33] .

discussing in your review the approaches, limitations, and conclusions of past reviews,

trying to find a new angle that has not been covered adequately in the previous reviews, and

incorporating new material that has inevitably accumulated since their appearance.

When searching the literature for pertinent papers and reviews, the usual rules apply:

be thorough,

use different keywords and database sources (e.g., DBLP, Google Scholar, ISI Proceedings, JSTOR Search, Medline, Scopus, Web of Science), and

look at who has cited past relevant papers and book chapters.

Rule 3: Take Notes While Reading

If you read the papers first, and only afterwards start writing the review, you will need a very good memory to remember who wrote what, and what your impressions and associations were while reading each single paper. My advice is, while reading, to start writing down interesting pieces of information, insights about how to organize the review, and thoughts on what to write. This way, by the time you have read the literature you selected, you will already have a rough draft of the review.

Of course, this draft will still need much rewriting, restructuring, and rethinking to obtain a text with a coherent argument [11] , but you will have avoided the danger posed by staring at a blank document. Be careful when taking notes to use quotation marks if you are provisionally copying verbatim from the literature. It is advisable then to reformulate such quotes with your own words in the final draft. It is important to be careful in noting the references already at this stage, so as to avoid misattributions. Using referencing software from the very beginning of your endeavour will save you time.

Rule 4: Choose the Type of Review You Wish to Write

After having taken notes while reading the literature, you will have a rough idea of the amount of material available for the review. This is probably a good time to decide whether to go for a mini- or a full review. Some journals are now favouring the publication of rather short reviews focusing on the last few years, with a limit on the number of words and citations. A mini-review is not necessarily a minor review: it may well attract more attention from busy readers, although it will inevitably simplify some issues and leave out some relevant material due to space limitations. A full review will have the advantage of more freedom to cover in detail the complexities of a particular scientific development, but may then be left in the pile of the very important papers “to be read” by readers with little time to spare for major monographs.

There is probably a continuum between mini- and full reviews. The same point applies to the dichotomy of descriptive vs. integrative reviews. While descriptive reviews focus on the methodology, findings, and interpretation of each reviewed study, integrative reviews attempt to find common ideas and concepts from the reviewed material [12] . A similar distinction exists between narrative and systematic reviews: while narrative reviews are qualitative, systematic reviews attempt to test a hypothesis based on the published evidence, which is gathered using a predefined protocol to reduce bias [13] , [14] . When systematic reviews analyse quantitative results in a quantitative way, they become meta-analyses. The choice between different review types will have to be made on a case-by-case basis, depending not just on the nature of the material found and the preferences of the target journal(s), but also on the time available to write the review and the number of coauthors [15] .

Rule 5: Keep the Review Focused, but Make It of Broad Interest

Whether your plan is to write a mini- or a full review, it is good advice to keep it focused 16 , 17 . Including material just for the sake of it can easily lead to reviews that are trying to do too many things at once. The need to keep a review focused can be problematic for interdisciplinary reviews, where the aim is to bridge the gap between fields [18] . If you are writing a review on, for example, how epidemiological approaches are used in modelling the spread of ideas, you may be inclined to include material from both parent fields, epidemiology and the study of cultural diffusion. This may be necessary to some extent, but in this case a focused review would only deal in detail with those studies at the interface between epidemiology and the spread of ideas.

While focus is an important feature of a successful review, this requirement has to be balanced with the need to make the review relevant to a broad audience. This square may be circled by discussing the wider implications of the reviewed topic for other disciplines.

Rule 6: Be Critical and Consistent

Reviewing the literature is not stamp collecting. A good review does not just summarize the literature, but discusses it critically, identifies methodological problems, and points out research gaps [19] . After having read a review of the literature, a reader should have a rough idea of:

the major achievements in the reviewed field,

the main areas of debate, and

the outstanding research questions.

It is challenging to achieve a successful review on all these fronts. A solution can be to involve a set of complementary coauthors: some people are excellent at mapping what has been achieved, some others are very good at identifying dark clouds on the horizon, and some have instead a knack at predicting where solutions are going to come from. If your journal club has exactly this sort of team, then you should definitely write a review of the literature! In addition to critical thinking, a literature review needs consistency, for example in the choice of passive vs. active voice and present vs. past tense.

Rule 7: Find a Logical Structure

Like a well-baked cake, a good review has a number of telling features: it is worth the reader's time, timely, systematic, well written, focused, and critical. It also needs a good structure. With reviews, the usual subdivision of research papers into introduction, methods, results, and discussion does not work or is rarely used. However, a general introduction of the context and, toward the end, a recapitulation of the main points covered and take-home messages make sense also in the case of reviews. For systematic reviews, there is a trend towards including information about how the literature was searched (database, keywords, time limits) [20] .

How can you organize the flow of the main body of the review so that the reader will be drawn into and guided through it? It is generally helpful to draw a conceptual scheme of the review, e.g., with mind-mapping techniques. Such diagrams can help recognize a logical way to order and link the various sections of a review [21] . This is the case not just at the writing stage, but also for readers if the diagram is included in the review as a figure. A careful selection of diagrams and figures relevant to the reviewed topic can be very helpful to structure the text too [22] .

Rule 8: Make Use of Feedback

Reviews of the literature are normally peer-reviewed in the same way as research papers, and rightly so [23] . As a rule, incorporating feedback from reviewers greatly helps improve a review draft. Having read the review with a fresh mind, reviewers may spot inaccuracies, inconsistencies, and ambiguities that had not been noticed by the writers due to rereading the typescript too many times. It is however advisable to reread the draft one more time before submission, as a last-minute correction of typos, leaps, and muddled sentences may enable the reviewers to focus on providing advice on the content rather than the form.

Feedback is vital to writing a good review, and should be sought from a variety of colleagues, so as to obtain a diversity of views on the draft. This may lead in some cases to conflicting views on the merits of the paper, and on how to improve it, but such a situation is better than the absence of feedback. A diversity of feedback perspectives on a literature review can help identify where the consensus view stands in the landscape of the current scientific understanding of an issue [24] .

Rule 9: Include Your Own Relevant Research, but Be Objective

In many cases, reviewers of the literature will have published studies relevant to the review they are writing. This could create a conflict of interest: how can reviewers report objectively on their own work [25] ? Some scientists may be overly enthusiastic about what they have published, and thus risk giving too much importance to their own findings in the review. However, bias could also occur in the other direction: some scientists may be unduly dismissive of their own achievements, so that they will tend to downplay their contribution (if any) to a field when reviewing it.

In general, a review of the literature should neither be a public relations brochure nor an exercise in competitive self-denial. If a reviewer is up to the job of producing a well-organized and methodical review, which flows well and provides a service to the readership, then it should be possible to be objective in reviewing one's own relevant findings. In reviews written by multiple authors, this may be achieved by assigning the review of the results of a coauthor to different coauthors.

Rule 10: Be Up-to-Date, but Do Not Forget Older Studies

Given the progressive acceleration in the publication of scientific papers, today's reviews of the literature need awareness not just of the overall direction and achievements of a field of inquiry, but also of the latest studies, so as not to become out-of-date before they have been published. Ideally, a literature review should not identify as a major research gap an issue that has just been addressed in a series of papers in press (the same applies, of course, to older, overlooked studies (“sleeping beauties” [26] )). This implies that literature reviewers would do well to keep an eye on electronic lists of papers in press, given that it can take months before these appear in scientific databases. Some reviews declare that they have scanned the literature up to a certain point in time, but given that peer review can be a rather lengthy process, a full search for newly appeared literature at the revision stage may be worthwhile. Assessing the contribution of papers that have just appeared is particularly challenging, because there is little perspective with which to gauge their significance and impact on further research and society.

Inevitably, new papers on the reviewed topic (including independently written literature reviews) will appear from all quarters after the review has been published, so that there may soon be the need for an updated review. But this is the nature of science [27] – [32] . I wish everybody good luck with writing a review of the literature.

Acknowledgments

Many thanks to M. Barbosa, K. Dehnen-Schmutz, T. Döring, D. Fontaneto, M. Garbelotto, O. Holdenrieder, M. Jeger, D. Lonsdale, A. MacLeod, P. Mills, M. Moslonka-Lefebvre, G. Stancanelli, P. Weisberg, and X. Xu for insights and discussions, and to P. Bourne, T. Matoni, and D. Smith for helpful comments on a previous draft.

Funding Statement

This work was funded by the French Foundation for Research on Biodiversity (FRB) through its Centre for Synthesis and Analysis of Biodiversity data (CESAB), as part of the NETSEED research project. The funders had no role in the preparation of the manuscript.

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• To introduce the source, its main ideas, key details, and its place within the field
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In general, the introduction of your critical review should include

• Author(s) name
• Title of the source 
• What is the author's central purpose?
• What methods or theoretical frameworks were used to accomplish this purpose?
• What topic areas, chapters, sections, or key points did the author use to structure the source?
• What were the results or findings of the study?
• How were the results or findings interpreted? How were they related to the original problem (author's view of evidence rather than objective findings)?
• Who conducted the research? What were/are their interests?
• Why did they do this research?
• Was this research pertinent only within the author’s field, or did it have broader (even global) relevance?
• On what prior research was this source-based? What gap is the author attempting to address?
• How important was the research question posed by the researcher?
• Your overall opinion of the quality of the source. Think of this like a thesis or main argument.
• Present your evaluation of the source, providing evidence from the text (or other sources) to support your assessment.

In general, the body of your critical review should include

• Is the material organized logically and with appropriate headings?
• Are there stylistic problems in logical, clarity or language?
• Were the author(s) able to answer the question (test the hypothesis) raised
• What was the objective of the study?
• Does all the information lead coherently to the purpose of the study?
• Are the methods valid for studying the problem or gap?
• Could the study be duplicated from the information provided?
• Is the experimental design logical and reliable?
• How are the data organized? Is it logical and interpretable?
• Do the results reveal what the researcher intended?
• Do the authors present a logical interpretation of the results?
• Have the limitations of the research been addressed?
• Does the study consider other key studies in the field or other research possibilities or directions?
• How was the significance of the work described?
• Follow the structure of the journal article (e.g. Introduction, Methods, Results, Discussion) - highlighting the strengths and weaknesses in each section
• Present the weaknesses of the article, and then the strengths of the article (or vice versa).
• Group your ideas according to different research themes presented in the source
• Group the strengths and weaknesses of the article into the following areas: originality, reliability, validity, relevance, and presentation

Purpose: 

• To summarize the strengths and weaknesses of the article as a whole
• To assert the article’s practical and theoretical significance

In general, the conclusion of your critical review should include

• A restatement of your overall opinion
• A summary of the key strengths and weaknesses of the research that support your overall opinion of the source
• Did the research reported in this source result in the formation of new questions, theories or hypotheses by the authors or other researchers?
• Have other researchers subsequently supported or refuted the observations or interpretations of these authors?
• Did the research provide new factual information, a new understanding of a phenomenon in the field, a new research technique?
• Did the research produce any practical applications? 
• What are the social, political, technological, or medical implications of this research?
• How do you evaluate the significance of the research? 
• Find out what style guide you are required to follow (e.g., APA, MLA, Chicago) and follow the guidelines to create a reference list (may be called a bibliography or works cited).
• Be sure to include citations in the text when you refer to the source itself or external sources. 
• Check out our Cite Your Sources Guide for more information. 
• Read assignment instructions carefully and refer to them throughout the writing process.
• Make an outline of your main sections before you write.
• If your professor does not assign a topic or source, you must choose one yourself. Select a source that interests you and is written clearly so you can understand it.
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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: .

• 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: 
• How to write a literature review faster with Paperpal? 

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.

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

1. 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. 

2. 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.

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3. 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. 

4. 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. 

5. 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. 

6. 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: 

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. 

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. 

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. 

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. 

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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. 

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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. 

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How to write a literature review faster with Paperpal?  

Paperpal, an AI writing assistant, integrates powerful academic search capabilities within its writing platform. With the Research | Cite feature, you get 100% factual insights, with citations backed by 250M+ verified research articles, directly within your writing interface. It also allows you auto-cite references in 10,000+ styles and save relevant references in your Citation Library. By eliminating the need to switch tabs to find answers to all your research questions, Paperpal saves time and helps you stay focused on your writing.   

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• Review and Save: Paperpal summarizes the information, while citing sources and listing relevant reads. You can quickly scan the results to identify relevant references and save these directly to your built-in citations library for later access. 
• Cite with Confidence: Paperpal makes it easy to incorporate relevant citations and references in 10,000+ styles into your writing, ensuring your arguments are well-supported by credible sources. This translates to a polished, well-researched literature review. 

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 good literature review is an ongoing process, and it may be necessary to revisit and update it as your research progresses. By combining effortless research with an easy citation process, Paperpal Research streamlines the literature review process and empowers you to write faster and with more confidence. Try Paperpal Research now and see for yourself.  

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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