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• How to Write a Literature Review | Guide, Examples, & Templates

How to Write a Literature Review | Guide, Examples, & Templates

Published on January 2, 2023 by Shona McCombes . Revised on September 11, 2023.

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 that you can later apply to your paper, thesis, or dissertation topic .

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 summarize sources—it analyzes, synthesizes , and critically evaluates to give a clear picture of the state of knowledge on the subject.

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Table of contents

What is the purpose of 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, free lecture slides, other interesting articles, frequently asked questions, introduction.

• Quick Run-through
• Step 1 & 2

When you write a thesis , dissertation , or research paper , you will likely 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 its scholarly context
• Develop a theoretical framework and methodology for your research
• Position your work in relation to other researchers and theorists
• Show how your research addresses a gap or contributes to a debate
• Evaluate the current state of research and demonstrate your knowledge of the scholarly debates around your topic.

Writing literature reviews is a particularly important skill if you want to apply for graduate school or pursue a career in research. We’ve written a step-by-step guide that you can follow below.

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See an example

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 problem and questions .

Make a list of keywords

Start by creating a list of keywords related to your research question. 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 as 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 useful 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 also use boolean operators to help narrow down your search.

Make sure to 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.

You likely won’t be able to read absolutely everything that has been written on your topic, so it will be necessary to evaluate which sources are most relevant to your research question.

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?
• 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 use our template to summarize and evaluate sources you’re thinking about using. Click on either button below to download.

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 is important to keep track of your sources with citations to avoid plagiarism . It can be helpful to make an annotated bibliography , where you compile full citation 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.

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To begin organizing your literature review’s argument and structure, be sure you 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 organizing the body of a literature review. 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 summarizing sources in order.

Try to analyze 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 organize 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.

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, you can follow these tips:

• 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 sentences to draw connections, comparisons and contrasts

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

When you’ve finished writing and revising your literature review, don’t forget to proofread thoroughly before submitting. Not a language expert? Check out Scribbr’s professional proofreading services !

This article has been adapted into lecture slides that you can use to teach your students about writing a literature review.

Scribbr slides are free to use, customize, and distribute for educational purposes.

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If you want to know more about the research process , methodology , research bias , or statistics , make sure to check out some of our other articles with explanations and examples.

• Sampling methods
• Simple random sampling
• Stratified sampling
• Cluster sampling
• Likert scales
• Reproducibility

 Statistics

• Null hypothesis
• Statistical power
• Probability distribution
• Effect size
• Poisson distribution

Research bias

• Optimism bias
• Cognitive bias
• Implicit bias
• Hawthorne effect
• Anchoring bias
• Explicit bias

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 thesis, dissertation , or research paper , in order to situate your work in relation to existing knowledge.

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

• To familiarize 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 thesis or dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

A literature review is a survey of credible sources on a topic, often used in dissertations , theses, and research papers . Literature reviews give an overview of knowledge on a subject, helping you identify relevant theories and methods, as well as gaps in existing research. Literature reviews are set up similarly to other  academic texts , with an introduction , a main body, and a conclusion .

An  annotated bibliography is a list of  source references that has a short description (called an annotation ) for each of the sources. It is often assigned as part of the research process for a  paper .  

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How Do I Write the Discussion Chapter?

Reflecting on and Comparing Your Data, Recognising the Strengths and Limitations

• First Online: 19 October 2023

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The Discussion chapter brings an opportunity to write an academic argument that contains a detailed critical evaluation and analysis of your research findings. This chapter addresses the purpose and critical nature of the discussion, contains a guide to selecting key results to discuss, and details how best to structure the discussion with subsections and paragraphs. We also present a list of points to do and avoid when writing the discussion together with a Discussion chapter checklist.

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Cottrell S (2017) Critical thinking skills: effective analysis, argument and reflection, 3rd edn. Palgrave, London

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How to write a superb literature review

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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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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).

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How to write a discussion section?

Writing manuscripts to describe study outcomes, although not easy, is the main task of an academician. The aim of the present review is to outline the main aspects of writing the discussion section of a manuscript. Additionally, we address various issues regarding manuscripts in general. It is advisable to work on a manuscript regularly to avoid losing familiarity with the article. On principle, simple, clear and effective language should be used throughout the text. In addition, a pre-peer review process is recommended to obtain feedback on the manuscript. The discussion section can be written in 3 parts: an introductory paragraph, intermediate paragraphs and a conclusion paragraph. For intermediate paragraphs, a “divide and conquer” approach, meaning a full paragraph describing each of the study endpoints, can be used. In conclusion, academic writing is similar to other skills, and practice makes perfect.

Introduction

Sharing knowledge produced during academic life is achieved through writing manuscripts. However writing manuscripts is a challenging endeavour in that we physicians have a heavy workload, and English which is common language used for the dissemination of scientific knowledge is not our mother tongue.

The objective of this review is to summarize the method of writing ‘Discussion’ section which is the most important, but probably at the same time the most unlikable part of a manuscript, and demonstrate the easy ways we applied in our practice, and finally share the frequently made relevant mistakes. During this procedure, inevitably some issues which concerns general concept of manuscript writing process are dealt with. Therefore in this review we will deal with topics related to the general aspects of manuscript writing process, and specifically issues concerning only the ‘Discussion’ section.

A) Approaches to general aspects of manuscript writing process:

1. what should be the strategy of sparing time for manuscript writing be.

Two different approaches can be formulated on this issue? One of them is to allocate at least 30 minutes a day for writing a manuscript which amounts to 3.5 hours a week. This period of time is adequate for completion of a manuscript within a few weeks which can be generally considered as a long time interval. Fundamental advantage of this approach is to gain a habit of making academic researches if one complies with the designated time schedule, and to keep the manuscript writing motivation at persistently high levels. Another approach concerning this issue is to accomplish manuscript writing process within a week. With the latter approach, the target is rapidly attained. However longer time periods spent in order to concentrate on the subject matter can be boring, and lead to loss of motivation. Daily working requirements unrelated to the manuscript writing might intervene, and prolong manuscript writing process. Alienation periods can cause loss of time because of need for recurrent literature reviews. The most optimal approach to manuscript writing process is daily writing strategy where higher levels of motivation are persistently maintained.

Especially before writing the manuscript, the most important step at the start is to construct a draft, and completion of the manuscript on a theoretical basis. Therefore, during construction of a draft, attention distracting environment should be avoided, and this step should be completed within 1–2 hours. On the other hand, manuscript writing process should begin before the completion of the study (even the during project stage). The justification of this approach is to see the missing aspects of the study and the manuscript writing methodology, and try to solve the relevant problems before completion of the study. Generally, after completion of the study, it is very difficult to solve the problems which might be discerned during the writing process. Herein, at least drafts of the ‘Introduction’, and ‘Material and Methods’ can be written, and even tables containing numerical data can be constructed. These tables can be written down in the ‘Results’ section. [ 1 ]

2. How should the manuscript be written?

The most important principle to be remembered on this issue is to obey the criteria of simplicity, clarity, and effectiveness. [ 2 ] Herein, do not forget that, the objective should be to share our findings with the readers in an easily comprehensible format. Our approach on this subject is to write all structured parts of the manuscript at the same time, and start writing the manuscript while reading the first literature. Thus newly arisen connotations, and self-brain gyms will be promptly written down. However during this process your outcomes should be revealed fully, and roughly the message of the manuscript which be delivered. Thus with this so-called ‘hunter’s approach’ the target can be achieved directly, and rapidly. Another approach is ‘collectioner’s approach. [ 3 ] In this approach, firstly, potential data, and literature studies are gathered, read, and then selected ones are used. Since this approach suits with surgical point of view, probably ‘hunter’s approach’ serves our purposes more appropriately. However, in parallel with academic development, our novice colleague ‘manuscripters’ can prefer ‘collectioner’s approach.’

On the other hand, we think that research team consisting of different age groups has some advantages. Indeed young colleagues have the enthusiasm, and energy required for the conduction of the study, while middle-aged researchers have the knowledge to manage the research, and manuscript writing. Experienced researchers make guiding contributions to the manuscript. However working together in harmony requires assignment of a chief researcher, and periodically organizing advancement meetings. Besides, talents, skills, and experiences of the researchers in different fields (ie. research methods, contact with patients, preparation of a project, fund-raising, statistical analysis etc.) will determine task sharing, and make a favourable contribution to the perfection of the manuscript. Achievement of the shared duties within a predetermined time frame will sustain the motivation of the researchers, and prevent wearing out of updated data.

According to our point of view, ‘Abstract’ section of the manuscript should be written after completion of the manuscript. The reason for this is that during writing process of the main text, the significant study outcomes might become insignificant or vice versa. However, generally, before onset of the writing process of the manuscript, its abstract might be already presented in various congresses. During writing process, this abstract might be a useful guide which prevents deviation from the main objective of the manuscript.

On the other hand references should be promptly put in place while writing the manuscript, Sorting, and placement of the references should not be left to the last moment. Indeed, it might be very difficult to remember relevant references to be placed in the ‘Discussion’ section. For the placement of references use of software programs detailed in other sections is a rational approach.

3. Which target journal should be selected?

In essence, the methodology to be followed in writing the ‘Discussion’ section is directly related to the selection of the target journal. Indeed, in compliance with the writing rules of the target journal, limitations made on the number of words after onset of the writing process, effects mostly the ‘Discussion’ section. Proper matching of the manuscript with the appropriate journal requires clear, and complete comprehension of the available data from scientific point of view. Previously, similar articles might have been published, however innovative messages, and new perspectives on the relevant subject will facilitate acceptance of the article for publication. Nowadays, articles questioning available information, rather than confirmatory ones attract attention. However during this process, classical information should not be questioned except for special circumstances. For example manuscripts which lead to the conclusions as “laparoscopic surgery is more painful than open surgery” or “laparoscopic surgery can be performed without prior training” will not be accepted or they will be returned by the editor of the target journal to the authors with the request of critical review. Besides the target journal to be selected should be ready to accept articles with similar concept. In fact editors of the journal will not reserve the limited space in their journal for articles yielding similar conclusions.

The title of the manuscript is as important as the structured sections * of the manuscript. The title can be the most striking or the newest outcome among results obtained.

Before writing down the manuscript, determination of 2–3 titles increases the motivation of the authors towards the manuscript. During writing process of the manuscript one of these can be selected based on the intensity of the discussion. However the suitability of the title to the agenda of the target journal should be investigated beforehand. For example an article bearing the title “Use of barbed sutures in laparoscopic partial nephrectomy shortens warm ischemia time” should not be sent to “Original Investigations and Seminars in Urologic Oncology” Indeed the topic of the manuscript is out of the agenda of this journal.

4. Do we have to get a pre-peer review about the written manuscript?

Before submission of the manuscript to the target journal the opinions of internal, and external referees should be taken. [ 1 ] Internal referees can be considered in 2 categories as “General internal referees” and “expert internal referees” General internal referees (ie. our colleagues from other medical disciplines) are not directly concerned with your subject matter but as mentioned above they critically review the manuscript as for simplicity, clarity, and effectiveness of its writing style. Expert internal reviewers have a profound knowledge about the subject, and they can provide guidance about the writing process of the manuscript (ie. our senior colleagues more experienced than us). External referees are our colleagues who did not contribute to data collection of our study in any way, but we can request their opinions about the subject matter of the manuscript. Since they are unrelated both to the author(s), and subject matter of the manuscript, these referees can review our manuscript more objectively. Before sending the manuscript to internal, and external referees, we should contact with them, and ask them if they have time to review our manuscript. We should also give information about our subject matter. Otherwise pre-peer review process can delay publication of the manuscript, and decrease motivation of the authors. In conclusion, whoever the preferred referee will be, these internal, and external referees should respond the following questions objectively. 1) Does the manuscript contribute to the literature?; 2) Does it persuasive? 3) Is it suitable for the publication in the selected journal? 4) Has a simple, clear, and effective language been used throughout the manuscript? In line with the opinions of the referees, the manuscript can be critically reviewed, and perfected. [ 1 ]**

Following receival of the opinions of internal, and external referees, one should concentrate priorly on indicated problems, and their solutions. Comments coming from the reviewers should be criticized, but a defensive attitude should not be assumed during this evaluation process. During this “incubation” period where the comments of the internal, and external referees are awaited, literature should be reviewed once more. Indeed during this time interval a new article which you should consider in the ‘Discussion’ section can be cited in the literature.

5. What are the common mistakes made related to the writing process of a manuscript?

Probably the most important mistakes made related to the writing process of a manuscript include lack of a clear message of the manuscript , inclusion of more than one main idea in the same text or provision of numerous unrelated results at the same time so as to reinforce the assertions of the manuscript. This approach can be termed roughly as “loss of the focus of the study” In conclusion, the author(s) should ask themselves the following question at every stage of the writing process:. “What is the objective of the study? If you always get clear-cut answers whenever you ask this question, then the study is proceeding towards the right direction. Besides application of a template which contains the intended clear-cut messages to be followed will contribute to the communication of net messages.

One of the important mistakes is refraining from critical review of the manuscript as a whole after completion of the writing process. Therefore, the authors should go over the manuscript for at least three times after finalization of the manuscript based on joint decision. The first control should concentrate on the evaluation of the appropriateness of the logic of the manuscript, and its organization, and whether desired messages have been delivered or not. Secondly, syutax, and grammar of the manuscript should be controlled. It is appropriate to review the manuscript for the third time 1 or 2 weeks after completion of its writing process. Thus, evaluation of the “cooled” manuscript will be made from a more objective perspective, and assessment process of its integrity will be facilitated.

Other erroneous issues consist of superfluousness of the manuscript with unnecessary repetitions, undue, and recurrent references to the problems adressed in the manuscript or their solution methods, overcriticizing or overpraising other studies, and use of a pompous literary language overlooking the main objective of sharing information. [ 4 ]

B) Approaches to the writing process of the ‘Discussion’ section:

1. how should the main points of ‘discussion’ section be constructed.

Generally the length of the ‘Discussion ‘ section should not exceed the sum of other sections (ıntroduction, material and methods, and results), and it should be completed within 6–7 paragraphs.. Each paragraph should not contain more than 200 words, and hence words should be counted repeteadly. The ‘Discussion’ section can be generally divided into 3 separate paragraphs as. 1) Introductory paragraph, 2) Intermediate paragraphs, 3) Concluding paragraph.

The introductory paragraph contains the main idea of performing the study in question. Without repeating ‘Introduction’ section of the manuscript, the problem to be addressed, and its updateness are analysed. The introductory paragraph starts with an undebatable sentence, and proceeds with a part addressing the following questions as 1) On what issue we have to concentrate, discuss or elaborate? 2) What solutions can be recommended to solve this problem? 3) What will be the new, different, and innovative issue? 4) How will our study contribute to the solution of this problem An introductory paragraph in this format is helpful to accomodate reader to the rest of the Discussion section. However summarizing the basic findings of the experimental studies in the first paragraph is generally recommended by the editors of the journal. [ 5 ]

In the last paragraph of the Discussion section “strong points” of the study should be mentioned using “constrained”, and “not too strongly assertive” statements. Indicating limitations of the study will reflect objectivity of the authors, and provide answers to the questions which will be directed by the reviewers of the journal. On the other hand in the last paragraph, future directions or potential clinical applications may be emphasized.

2. How should the intermediate paragraphs of the Discussion section be formulated?

The reader passes through a test of boredom while reading paragraphs of the Discussion section apart from the introductory, and the last paragraphs. Herein your findings rather than those of the other researchers are discussed. The previous studies can be an explanation or reinforcement of your findings. Each paragraph should contain opinions in favour or against the topic discussed, critical evaluations, and learning points.

Our management approach for intermediate paragraphs is “divide and conquer” tactics. Accordingly, the findings of the study are determined in order of their importance, and a paragraph is constructed for each finding ( Figure 1 ). Each paragraph begins with an “indisputable” introductory sentence about the topic to be discussed. This sentence basically can be the answer to the question “What have we found?” Then a sentence associated with the subject matter to be discussed is written. Subsequently, in the light of the current literature this finding is discussed, new ideas on this subject are revealed, and the paragraph ends with a concluding remark.

Divide and Conquer tactics

In this paragraph, main topic should be emphasized without going into much detail. Its place, and importance among other studies should be indicated. However during this procedure studies should be presented in a logical sequence (ie. from past to present, from a few to many cases), and aspects of the study contradictory to other studies should be underlined. Results without any supportive evidence or equivocal results should not be written. Besides numerical values presented in the Results section should not be repeated unless required.

Besides, asking the following questions, and searching their answers in the same paragraph will facilitate writing process of the paragraph. [ 1 ] 1) Can the discussed result be false or inadequate? 2) Why is it false? (inadequate blinding, protocol contamination, lost to follow-up, lower statistical power of the study etc.), 3) What meaning does this outcome convey?

3. What are the common mistakes made in writing the Discussion section?:

Probably the most important mistake made while writing the Discussion section is the need for mentioning all literature references. One point to remember is that we are not writing a review article, and only the results related to this paragraph should be discussed. Meanwhile, each word of the paragraphs should be counted, and placed carefully. Each word whose removal will not change the meaning should be taken out from the text.” Writing a saga with “word salads” *** is one of the reasons for prompt rejection. Indeed, if the reviewer thinks that it is difficult to correct the Discussion section, he/she use her/ his vote in the direction of rejection to save time (Uniform requirements for manuscripts: International Comittee of Medical Journal Editors [ http://www.icmje.org/urm_full.pdf ])

The other important mistake is to give too much references, and irrelevancy between the references, and the section with these cited references. [ 3 ] While referring these studies, (excl. introductory sentences linking indisputable sentences or paragraphs) original articles should be cited. Abstracts should not be referred, and review articles should not be cited unless required very much.

4. What points should be paid attention about writing rules, and grammar?

As is the case with the whole article, text of the Discussion section should be written with a simple language, as if we are talking with our colleague. [ 2 ] Each sentence should indicate a single point, and it should not exceed 25–30 words. The priorly mentioned information which linked the previous sentence should be placed at the beginning of the sentence, while the new information should be located at the end of the sentence. During construction of the sentences, avoid unnecessary words, and active voice rather than passive voice should be used.**** Since conventionally passive voice is used in the scientific manuscripts written in the Turkish language, the above statement contradicts our writing habits. However, one should not refrain from beginning the sentences with the word “we”. Indeed, editors of the journal recommend use of active voice so as to increase the intelligibility of the manuscript.

In conclusion, the major point to remember is that the manuscript should be written complying with principles of simplicity, clarity, and effectiveness. In the light of these principles, as is the case in our daily practice, all components of the manuscript (IMRAD) can be written concurrently. In the ‘Discussion’ section ‘divide and conquer’ tactics remarkably facilitates writing process of the discussion. On the other hand, relevant or irrelevant feedbacks received from our colleagues can contribute to the perfection of the manuscript. Do not forget that none of the manuscripts is perfect, and one should not refrain from writing because of language problems, and related lack of experience.

Instead of structured sections of a manuscript (IMRAD): Introduction, Material and Methods, Results, and Discussion

Instead of in the Istanbul University Faculty of Medicine posters to be submitted in congresses are time to time discussed in Wednesday meetings, and opinions of the internal referees are obtained about the weak, and strong points of the study

Instead of a writing style which uses words or sentences with a weak logical meaning that do not lead the reader to any conclusion

Instead of “white color”; “proven”; nstead of “history”; “to”. should be used instead of “white in color”, “definitely proven”, “past history”, and “in order to”, respectively ( ref. 2 )

Instead of “No instances of either postoperative death or major complications occurred during the early post-operative period” use “There were no deaths or major complications occurred during the early post-operative period.

Instead of “Measurements were performed to evaluate the levels of CEA in the serum” use “We measured serum CEA levels”

• 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

Literature Review Tips for the Introduction and Discussion Sections

A literature review is a summary of studies related to a particular area of research. It identifies and summarizes all the relevant research conducted on a particular topic. It is important that your literature review is focused . Therefore, you should choose a limited number of studies that are central to your topic rather than trying to collect a wide range of studies that might not be closely connected.

Literature reviews help you accomplish the following:

• Evaluate past research  Collecting relevant resources will help you see what research has already been done. This will also help avoid duplication.
• Identify experts It is important to identify credible researchers who have knowledge in a given field, in order to seek their help if you get stuck with certain aspects of your research.
• Identify key questions  Your ultimate aim is to bring something new to the conversation. Collecting resources will help you determine the important questions that need to be addressed.
• Determine methodologies used in past studies Knowing how others have approached a particular topic will give you the opportunity to identify problems and find new ways to research and study a topic. If the reported methodology was successful, you can use it and save time that you would otherwise be spending on optimization.

Presenting Literature Review in the Introduction and Discussion Sections

There are many benefits to presenting literature reviews in the introduction and discussion sections of your manuscripts . However, there are differences in how you can present literature reviews in each section.

What Should be Included in the Literature Review of the Introduction Section?

The literature reviewed in the introduction should:

• Introduce the topic
• Establish the significance of the study
• Provide an overview of the relevant literature
• Establish a context for the study using the literature
• Identify knowledge gaps
• Illustrate how the study will advance knowledge on the topic

As you can see, literature review plays a significant role in the introduction section. However, there are some things that you should avoid doing in this section. These include:

• Elaborating on the studies mentioned in the literature review
• Using studies from the literature review to aggressively support your research
• Directly quoting studies from the literature review

It is important to know how to integrate the literature review into the introduction in an effective way. Although you can mention other studies, they should not be the focus. Instead, focus on using the literature review to aid in setting a foundation for the manuscript.

What Goes in the Literature Review of the Discussion Section?

Literature reviews play an important role in the discussion section of a manuscript . In this section, your findings should be the focus, rather than those of other researchers. Therefore, you should only use the studies mentioned in the literature review as support and evidence for your study.

There are three ways in which you can use literature reviews in the discussion section:

• To Provide Context for Your Study Using studies from the literature review helps to set the foundation for how you will reveal your findings and develop your ideas.
• Compare your Findings to Other Studies You can use previous literature as a backdrop to compare your new findings. This helps describe and also advance your ideas.
• State the Contribution of Your Study In addition to developing your ideas, you can use literature reviews to explain how your study contributes to the field of study.

However, there are three common mistakes that researchers make when including literature reviews in the discussion section. First, they mention all sorts of studies, some of which are not even relevant to the topic under investigation. Second, instead of citing the original article, they cite a related article that mentions the original article. Lastly, some authors cite previous work solely based on the abstract, without even going through the entire paper.

We hope this article helps you effectively present your literature review in both the introduction as well as the discussion section of your manuscript. You can also mention any other tips that will add to this article in the comments section below.

References:

[1]  http://www.math.montana.edu/jobo/phdprep/documents/phd6.pdf 

[2]  https://libguides.unf.edu/c.php?g=177129&p=1163732

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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.

What Is A Literature Review?

A plain-language explainer (with examples).

By:  Derek Jansen (MBA) & Kerryn Warren (PhD) | June 2020 (Updated May 2023)

If you’re faced with writing a dissertation or thesis, chances are you’ve encountered the term “literature review” . If you’re on this page, you’re probably not 100% what the literature review is all about. The good news is that you’ve come to the right place.

Literature Review 101

• What (exactly) is a literature review
• What’s the purpose of the literature review chapter
• How to find high-quality resources
• How to structure your literature review chapter
• Example of an actual literature review

What is a literature review?

The word “literature review” can refer to two related things that are part of the broader literature review process. The first is the task of  reviewing the literature  – i.e. sourcing and reading through the existing research relating to your research topic. The second is the  actual chapter  that you write up in your dissertation, thesis or research project. Let’s look at each of them:

Reviewing the literature

The first step of any literature review is to hunt down and  read through the existing research  that’s relevant to your research topic. To do this, you’ll use a combination of tools (we’ll discuss some of these later) to find journal articles, books, ebooks, research reports, dissertations, theses and any other credible sources of information that relate to your topic. You’ll then  summarise and catalogue these  for easy reference when you write up your literature review chapter. 

The literature review chapter

The second step of the literature review is to write the actual literature review chapter (this is usually the second chapter in a typical dissertation or thesis structure ). At the simplest level, the literature review chapter is an  overview of the key literature  that’s relevant to your research topic. This chapter should provide a smooth-flowing discussion of what research has already been done, what is known, what is unknown and what is contested in relation to your research topic. So, you can think of it as an  integrated review of the state of knowledge  around your research topic. 

What’s the purpose of a literature review?

The literature review chapter has a few important functions within your dissertation, thesis or research project. Let’s take a look at these:

Purpose #1 – Demonstrate your topic knowledge

The first function of the literature review chapter is, quite simply, to show the reader (or marker) that you  know what you’re talking about . In other words, a good literature review chapter demonstrates that you’ve read the relevant existing research and understand what’s going on – who’s said what, what’s agreed upon, disagreed upon and so on. This needs to be  more than just a summary  of who said what – it needs to integrate the existing research to  show how it all fits together  and what’s missing (which leads us to purpose #2, next). 

Purpose #2 – Reveal the research gap that you’ll fill

The second function of the literature review chapter is to  show what’s currently missing  from the existing research, to lay the foundation for your own research topic. In other words, your literature review chapter needs to show that there are currently “missing pieces” in terms of the bigger puzzle, and that  your study will fill one of those research gaps . By doing this, you are showing that your research topic is original and will help contribute to the body of knowledge. In other words, the literature review helps justify your research topic.  

Purpose #3 – Lay the foundation for your conceptual framework

The third function of the literature review is to form the  basis for a conceptual framework . Not every research topic will necessarily have a conceptual framework, but if your topic does require one, it needs to be rooted in your literature review. 

For example, let’s say your research aims to identify the drivers of a certain outcome – the factors which contribute to burnout in office workers. In this case, you’d likely develop a conceptual framework which details the potential factors (e.g. long hours, excessive stress, etc), as well as the outcome (burnout). Those factors would need to emerge from the literature review chapter – they can’t just come from your gut! 

So, in this case, the literature review chapter would uncover each of the potential factors (based on previous studies about burnout), which would then be modelled into a framework. 

Purpose #4 – To inform your methodology

The fourth function of the literature review is to  inform the choice of methodology  for your own research. As we’ve  discussed on the Grad Coach blog , your choice of methodology will be heavily influenced by your research aims, objectives and questions . Given that you’ll be reviewing studies covering a topic close to yours, it makes sense that you could learn a lot from their (well-considered) methodologies.

So, when you’re reviewing the literature, you’ll need to  pay close attention to the research design , methodology and methods used in similar studies, and use these to inform your methodology. Quite often, you’ll be able to  “borrow” from previous studies . This is especially true for quantitative studies , as you can use previously tried and tested measures and scales. 

How do I find articles for my literature review?

Finding quality journal articles is essential to crafting a rock-solid literature review. As you probably already know, not all research is created equally, and so you need to make sure that your literature review is  built on credible research . 

We could write an entire post on how to find quality literature (actually, we have ), but a good starting point is Google Scholar . Google Scholar is essentially the academic equivalent of Google, using Google’s powerful search capabilities to find relevant journal articles and reports. It certainly doesn’t cover every possible resource, but it’s a very useful way to get started on your literature review journey, as it will very quickly give you a good indication of what the  most popular pieces of research  are in your field.

One downside of Google Scholar is that it’s merely a search engine – that is, it lists the articles, but oftentimes  it doesn’t host the articles . So you’ll often hit a paywall when clicking through to journal websites. 

Thankfully, your university should provide you with access to their library, so you can find the article titles using Google Scholar and then search for them by name in your university’s online library. Your university may also provide you with access to  ResearchGate , which is another great source for existing research. 

Remember, the correct search keywords will be super important to get the right information from the start. So, pay close attention to the keywords used in the journal articles you read and use those keywords to search for more articles. If you can’t find a spoon in the kitchen, you haven’t looked in the right drawer. 

Need a helping hand?

How should I structure my literature review?

Unfortunately, there’s no generic universal answer for this one. The structure of your literature review will depend largely on your topic area and your research aims and objectives.

You could potentially structure your literature review chapter according to theme, group, variables , chronologically or per concepts in your field of research. We explain the main approaches to structuring your literature review here . You can also download a copy of our free literature review template to help you establish an initial structure.

In general, it’s also a good idea to start wide (i.e. the big-picture-level) and then narrow down, ending your literature review close to your research questions . However, there’s no universal one “right way” to structure your literature review. The most important thing is not to discuss your sources one after the other like a list – as we touched on earlier, your literature review needs to synthesise the research , not summarise it .

Ultimately, you need to craft your literature review so that it conveys the most important information effectively – it needs to tell a logical story in a digestible way. It’s no use starting off with highly technical terms and then only explaining what these terms mean later. Always assume your reader is not a subject matter expert and hold their hand through a journe y of the literature while keeping the functions of the literature review chapter (which we discussed earlier) front of mind.

Example of a literature review

In the video below, we walk you through a high-quality literature review from a dissertation that earned full distinction. This will give you a clearer view of what a strong literature review looks like in practice and hopefully provide some inspiration for your own. 

Wrapping Up

In this post, we’ve (hopefully) answered the question, “ what is a literature review? “. We’ve also considered the purpose and functions of the literature review, as well as how to find literature and how to structure the literature review chapter. If you’re keen to learn more, check out the literature review section of the Grad Coach blog , as well as our detailed video post covering how to write a literature review . 

Psst… there’s more!

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

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16 Comments

Thanks for this review. It narrates what’s not been taught as tutors are always in a early to finish their classes.

Thanks for the kind words, Becky. Good luck with your literature review 🙂

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Timothy T. Chol [email protected]

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Well-presented overview of the literature!

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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.

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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.
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A Guide to Writing the Dissertation Literature Review

• Justus Randolph

Writing a faulty literature review is one of many ways to derail a dissertation. This article summarizes some pivotal information on how to write a high-quality dissertation literature review. It begins with a discussion of the purposes of a review, presents taxonomy of literature reviews, and then discusses the steps in conducting a quantitative or qualitative literature review. The article concludes with a discussion of common mistakes and a framework for the self-evaluation of a literature review. Accessed 202,565 times on https://pareonline.net from June 04, 2009 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.

Keywords: Research Methodology

Randolph, J., (2009) “A Guide to Writing the Dissertation Literature Review”, Practical Assessment, Research, and Evaluation 14(1): 13. doi: https://doi.org/10.7275/b0az-8t74

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Published on 02 jan 2009, creative commons attribution-noncommercial-noderivatives 4.0, harvard-style citation.

Randolph, J. (2009) 'A Guide to Writing the Dissertation Literature Review', Practical Assessment, Research, and Evaluation . 14(1) doi: 10.7275/b0az-8t74

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• How to Write a Discussion Section | Tips & Examples

How to Write a Discussion Section | Tips & Examples

Published on 21 August 2022 by Shona McCombes . Revised on 25 October 2022.

The discussion section is where you delve into the meaning, importance, and relevance of your results .

It should focus on explaining and evaluating what you found, showing how it relates to your literature review , and making an argument in support of your overall conclusion . It should not be a second results section .

There are different ways to write this section, but you can focus your writing around these key elements:

• Summary: A brief recap of your key results
• Interpretations: What do your results mean?
• Implications: Why do your results matter?
• Limitations: What can’t your results tell us?
• Recommendations: Avenues for further studies or analyses

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Table of contents

What not to include in your discussion section, step 1: summarise your key findings, step 2: give your interpretations, step 3: discuss the implications, step 4: acknowledge the limitations, step 5: share your recommendations, discussion section example.

There are a few common mistakes to avoid when writing the discussion section of your paper.

• Don’t introduce new results: You should only discuss the data that you have already reported in your results section .
• Don’t make inflated claims: Avoid overinterpretation and speculation that isn’t directly supported by your data.
• Don’t undermine your research: The discussion of limitations should aim to strengthen your credibility, not emphasise weaknesses or failures.

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Start this section by reiterating your research problem  and concisely summarising your major findings. Don’t just repeat all the data you have already reported – aim for a clear statement of the overall result that directly answers your main  research question . This should be no more than one paragraph.

Many students struggle with the differences between a discussion section and a results section . The crux of the matter is that your results sections should present your results, and your discussion section should subjectively evaluate them. Try not to blend elements of these two sections, in order to keep your paper sharp.

• The results indicate that …
• The study demonstrates a correlation between …
• This analysis supports the theory that …
• The data suggest  that …

The meaning of your results may seem obvious to you, but it’s important to spell out their significance for your reader, showing exactly how they answer your research question.

The form of your interpretations will depend on the type of research, but some typical approaches to interpreting the data include:

• Identifying correlations , patterns, and relationships among the data
• Discussing whether the results met your expectations or supported your hypotheses
• Contextualising your findings within previous research and theory
• Explaining unexpected results and evaluating their significance
• Considering possible alternative explanations and making an argument for your position

You can organise your discussion around key themes, hypotheses, or research questions, following the same structure as your results section. Alternatively, you can also begin by highlighting the most significant or unexpected results.

• In line with the hypothesis …
• Contrary to the hypothesised association …
• The results contradict the claims of Smith (2007) that …
• The results might suggest that x . However, based on the findings of similar studies, a more plausible explanation is x .

As well as giving your own interpretations, make sure to relate your results back to the scholarly work that you surveyed in the literature review . The discussion should show how your findings fit with existing knowledge, what new insights they contribute, and what consequences they have for theory or practice.

Ask yourself these questions:

• Do your results support or challenge existing theories? If they support existing theories, what new information do they contribute? If they challenge existing theories, why do you think that is?
• Are there any practical implications?

Your overall aim is to show the reader exactly what your research has contributed, and why they should care.

• These results build on existing evidence of …
• The results do not fit with the theory that …
• The experiment provides a new insight into the relationship between …
• These results should be taken into account when considering how to …
• The data contribute a clearer understanding of …
• While previous research has focused on  x , these results demonstrate that y .

Even the best research has its limitations. Acknowledging these is important to demonstrate your credibility. Limitations aren’t about listing your errors, but about providing an accurate picture of what can and cannot be concluded from your study.

Limitations might be due to your overall research design, specific methodological choices , or unanticipated obstacles that emerged during your research process.

Here are a few common possibilities:

• If your sample size was small or limited to a specific group of people, explain how generalisability is limited.
• If you encountered problems when gathering or analysing data, explain how these influenced the results.
• If there are potential confounding variables that you were unable to control, acknowledge the effect these may have had.

After noting the limitations, you can reiterate why the results are nonetheless valid for the purpose of answering your research question.

• The generalisability of the results is limited by …
• The reliability of these data is impacted by …
• Due to the lack of data on x , the results cannot confirm …
• The methodological choices were constrained by …
• It is beyond the scope of this study to …

Based on the discussion of your results, you can make recommendations for practical implementation or further research. Sometimes, the recommendations are saved for the conclusion .

Suggestions for further research can lead directly from the limitations. Don’t just state that more studies should be done – give concrete ideas for how future work can build on areas that your own research was unable to address.

• Further research is needed to establish …
• Future studies should take into account …
• Avenues for future research include …

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• Writing Tips

Your Literature Review and Discussion Sections

3-minute read

• 23rd November 2015

Many things go well together in this world, like fish and chips or the birds and the bees (figuratively speaking). However, one felicitous pairing that might not immediately jump to mind are the literature review and discussion sections of your dissertation.

This is because a dissertation is more than a set of discrete essays; rather, each part should be written in a way that contributes to your dissertation as a greater whole. Nowhere is this more important than in the discussion section, as it’s essential to refer to your literature review when interpreting your results.

Why? Let us explain via the ‘Three C-Words’ (no, not that one: we’re talking about context, comparison and contribution).

1.     Context!

The main purpose of your literature review is to contextualise your research by outlining previous studies conducted in the field. Referring back to the literature review in your discussion section therefore helps set the background against which your results should be interpreted, making it easier to explain their relevance to your hypothesis.

2.     Comparison!

Simply describing your results isn’t enough in the discussion section, as you also need to interpret and analyse data in terms of your research question. One way to do this is by comparing your results to those obtained in similar studies.

For example, you might want to discuss whether your results agree or disagree with those of other researchers. If there is a difference, you’ll also want to consider why this has happened and whether it’s significant.

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However, you should not introduce new research in the discussion section. Make sure that any studies you refer to in the discussion have been addressed in the literature review. And don’t be afraid to modify your literature review as your study progresses (every dissertation project will evolve as it goes on).

3.     Contribution!

As well as discussing the relevance of your results, your discussion section should usually include some reference to how your research contributes to knowledge in your field of study.

This, again, requires that you refer to your literature review, where you have discussed existing research in your field. Ideally, you will also have formulated your research questions to address a gap in the current research. Your discussion section is thus where you explain how your results fill this gap.

In summary, referring to your literature review will make sure that your discussion section is always on topic. And remember the three C-words: context, comparison and contribution.

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Literature Review: Conducting & Writing

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Case report article, a 26-year-old man with multiple organ failure caused by aeromonas dhakensis infection: a case report and literature review.

• 1 Department of Respiratory and Critical Care Medicine, People’s Hospital of Chongqing Liang Jiang New Area, Chongqing, China
• 2 Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China

Background: Infections in humans are mainly caused by Aeromonas hydrophila , Aeromonas caviae , and Aeromonas veronii . In recent years, Aeromonas dhakensis has been recognized as widely distributed in the environment, with strong virulence. However, this bacterial infection usually does not appear in patients with pneumonia as the first symptom.

Case report: We report a 26-year-old man who was admitted to the hospital with community-acquired pneumonia as the first symptom and developed serious conditions such as hemolytic uremic syndrome, multiple organ dysfunction, and hemorrhagic shock within a short period. He died after 13 h of admission, and the subsequent metagenomic-next generation sequencing test confirmed the finally identified pathogen of infection as A. dhakensis .

Conclusion: Aeromonas is a rare pathogen identified in the diagnosis of community-acquired pneumonia. Hence, doctors need to develop their experience in identifying the difference between infections caused by pathogenic microorganisms. Medical attention is essential during the occurrence of respiratory symptoms that could be controlled by empirical drugs, such as cephalosporins or quinolones. When patients with community-acquired pneumonia present hemoptysis and multiple organ dysfunction in clinical treatment, an unusual pathogen infection should be considered, and the underlying etiology should be clarified at the earliest for timely treatment.

Graphical Abstract.

Introduction

Aeromonas dhakensis is a Gram-negative bacillus that is widely distributed in water environments. The mortality rate caused by infection with A. dhakensis is higher than that of other Aeromonas infections due to the abundance of virulence genes. It causes gastroenteritis, wound infection, sepsis, respiratory tract infection, hepatobiliary disease, urinary tract infection, muscle necrosis, rhabdomyolysis, necrotizing fasciitis, and the rare

hemolytic uremic syndrome. If an acute infection is not treated promptly, it may develop rapidly and lead to serious consequences. In this case study, we reported the onset and treatment of a 26-year-old patient infected with A. dhakensis .

Case report

A 26-year-old man with no history of lung diseases or other disorders was admitted to the local hospital due to cough and fatigue for 3 days, hemoptysis, dyspnea, fever, chest pain, and wheezing for a day. The patient was admitted to our emergency department. A blood routine examination showed that the white blood cell count was 7.06 × 10 9 /L, and the percentage of neutrophils was 69.9%. The liver function showed alanine aminotransferase at 150 U/L and aspartate transferase at 84 U/L, and the kidney function-related creatinine level was 197 mmol/L, and the uric acid level was 607 mmol/L. The coagulation function D-dimer level was 3730 ng/mL. Blood gas analysis (without oxygen) revealed the following: pH 7.32, PCO 2 43 mmHg, PO 2 37 mmHg, BE −3.9 mmol/L, HCO 3 22.21 mmol/L, Lac 4.8 mmol/L, SO 2 65%, Na + 132 mmol/L, K + 3.8 mmol/L, and Glu tendency of 7.1 mmol/L. The Chest computer tomography (CT) scan displayed a double lung infection ( Figure 1 ). A physical examination revealed a body temperature of 37.5°C, and vital signs were within normal range. Lucid, poor spirit, and wet rales could be heard in both lungs. After 2 h, the patient was transferred to the Respiratory Intensive Care Unit (RICU).

Figure 1. (a–h) The chest computer tomography (CT) scan displayed a double lung infection.

According to the examination, the patient was diagnosed with severe pneumonia and abnormal liver function. While being kept on a non-invasive ventilator, 1,000 mg of imipenem was given intravenously every 8 h, 600 mg of linezolid was given intravenously every 6 h, and reduced glutathione, polyene phosphatidylcholine, and carlo sulfonyl sodium were used. After transferring the patient to RICU post 2 h, the hemoptysis level increased to almost 100 ml, and blood gas analysis indicated respiratory failure. Thus, the patient received endotracheal intubation. Then, tracheoscopy was performed and active hemorrhage was observed in the right upper lobe opening. The lavage fluid was collected and cultured. The right upper lobe bronchus was blocked by a bronchoscope balloon, pituitrin, carlo sulfonyl sodium, and hemagglutinin to stop the bleeding.

Typically, the bleeding could be controlled, but it was counterproductive. The blood was drained from the stomach tube, the urine turned to a soy sauce color, and blood pressure dropped. Considering the patient had gastrointestinal bleeding and hemolysis, emergency blood transfusion measures were initiated, and vasoactive drugs were administered. To date, 1,000 ml of blood was aspirated under a bronchoscope, 300 ml from a gastric tube, and 150 ml was drained by the urinary tube, and the patient went into hemorrhagic shock. In addition, antishock treatment and extracorporeal membrane oxygenation (ECMO) were considered.

These measures stabilized the patient’s blood pressure at 80–95/50–55 mmHg, and the oxygen saturation was stabilized at 80%–90%. Indubitably, the patient’s condition deteriorated rapidly, leading to multiple organ failures before the initiation of ECMO therapy and eventually leading to death. At 6.3 h after death, the blood cultures suggested the presence of Aeromonas hydrophila/Aeromonas caviae ( Figure 2 ). At 33 h, irrigation fluid culture also signaled the presence of A. hydrophila/A. caviae after the patient’s death. This is the first case of Aeromonas infection that we have encountered and also a rare case of multiple organ failure reported in the literature.

Figure 2. (a) Gram-negative bacilli were observed under an oil immersion lens. (b) Gram-negative bacilli were observed under an oil immersion lens. (c) Gram-negative bacilli were observed under a microscope. (d) Medium colony.

Aeromonas is a Gram-negative bacillus widely distributed in freshwater, river/estuarine water (brackish water), surface water, drinking water, polluted water bodies, and sewage sludge ( 1 – 5 ). The classification includes A. hydrophila , A. caviae, Aeromonas veronii biovar sobria, Aeromonas milmiliae, Aeromonas salmonicides, Aeromonas intermedialis, Aeromonas janeii, Aeromonas shuiensis , and Aeromonas fragilis ( 6 ). Human infections are commonly caused by A. hydrophila , A. veronii biovar sobria , and A. caviae ( 7 ). The most common route of infection is contact with fresh or brackish water, which is usually stagnant in warm months (May–October in the Northern Hemisphere), its bacterial count reaches a peak value, thereby elevating the incidence of Aeromonas infection in summer ( 8 , 9 ). Patients with chronic underlying diseases, such as nephritis, diabetes, tumors, leukemia, and hepatobiliary pancreas, have low immunity and are at a high risk of Aeromonas infection. It directly enters the blood through the peritoneal barrier and reaches the thoracic tissue, pelvic tissue, lymph, gallbladder, and other parts. In severe cases, it may be life-threatening ( 10 ). The patient, in this case, was a 26-year-old man with no underlying diseases or low immunity. However, he had embarked on self-driving trips for 3 days before the onset of the disease. En route, he swam in a lake, which could be the cause of Aeromonas infection; the onset was rapid, and the clinical manifestations were critical.

Aeromonas cause a variety of human diseases such as diarrhea, wound infection, bacteremia, respiratory tract infection, eye infection, osteomyelitis, meningitis, pelvic abscess, otitis, cystitis, endocarditis, peritonitis, cholecystitis, joint infection, necrotizing fasciitis, and folliculitis ( 11 – 16 ). Diarrhea is the most common clinical manifestation. Different from the typical infection symptoms, this patient had respiratory symptoms of cough, expectoration, and hemoptysis as initial presentation, without diarrhea.

Within 11 h of admission, 1,000 ml of blood was aspirated under a bronchoscope, 300 ml of blood from the gastric tube, and 150 ml of blood was drained by the urinary tube. Subsequently, Aeromonas was detected in blood culture and bronchoscopic lavage fluid culture, and the biochemical results are shown in Table 1 . The results indicated that the patient was infected with Aeromona s, leading to Aeromonas hemolytic-uremic syndrome, which is a rare manifestation caused by this bacterium. Since A. hydrophila/A. caviae is often confused with A. dhakensis due to similar homology, conventional automatic laboratory biochemical identification cannot distinguish the species type effectively ( 17 ). Hence, metagenomic-next generation sequencing was recommended for species identification by whole genome sequencing. The results finally confirmed A. dhakensis infection in the patient.

Table 1. Biochemical identification of A. dhakensis .

It is a subspecies of A. hydrophila , also known as Aquariumonas . It was originally isolated from children with diarrhea in Bangladesh during the period of 1993–1994 ( 18 ). In Beaz-Hidalgo et al. ( 19 ), ascertained that the Dakar subspecies of A. hydrophila and A. aquarium were the same species and that the Dakar subspecies were different from other subspecies of A. hydrophila . Therefore, the Dakar subspecies of A. hydrophila and A. aquarium were merged into a new species of A. dhakensis ( 19 ). Accumulating evidence shows that A. dhakensis is widely distributed in the environment, primarily in coastal areas, and can cause various human and animal infections, including gastroenteritis, wound infection, sepsis, respiratory tract infection, hepatobiliary disease, urinary tract infection, muscle necrosis, rhabdomyolysis, and necrotizing fasciitis ( 20 ). The reported mortality rate among patients with A. dhakensis extraintestinal infection varies from 25.5% to 37.5%, which is much higher than in those infected with other Aeromonas species (0%–14%) ( 20 , 21 ). Previous studies reported that A. dhakensis carries several virulence factors and exerts high toxicity on human blood cell lines ( 22 – 25 ) via exotoxins (act, aerA, hlyA, alt, ast, and other genes), type III secretion system (aexT, aopP, ascF-G, ascV, and other genes), extracellular enzymes (gcat, exu, ahyB, lip, ser, epr CAI, and other genes), adhesion factors associated with invasion (tapA gene), and flagella (laf and fla genes) ( 7 ). The high mortality rate and the abundance of virulence genes make it a crucial pathogenic species. However, the pathogenesis mechanism and regulation of toxicity remain unclear ( 26 ). The majority of Aeromonas bacteria carry at least one virulence gene. Act, hlyA, aerA, gcat, and lip genes related to cytolysis were detected in both enteric Aeromonas and exenteric Aeromonas to varying degrees, which cause hemolysis in the body.

Aeromonas dhakensis is susceptible to cefepime, aminoglycosides, fluoroquinolones, and tetracyclines, and hence, these drugs can be used for the treatment of the infection ( 22 , 27 ). Chao et al. ( 28 ) indicated that more than 80% of clinical strains are sensitive to third- or fourth-generation cephalosporins, aminoglycosides, fluoroquinolones, and imipenems. Therefore, the above drugs are still the first choice for treatment. However, A. dhakensis intrinsically harbors class B (metallo-β-lactamases, MBLs; CphA), C (AmpC cephalosporinase; AQU-1), and D β-lactamases (penicillinases). CphA has a specific substrate profile for hydrolyzing carbapenems; however, carbapenem therapy using CphA on Aeromonas infections remains controversial ( 29 , 30 ). It is notable that ertapenem is a breakthrough in the treatment of bacteremia caused by A. dhakensis ( 29 ). The best antibacterial options for treating A. dhakensis infection include fluoroquinolone or cefepime until susceptibility results are available ( 20 ). For severe pneumonia cases, we chose imipenem and linezolid for anti-infection treatment. Combined with blood culture and drug sensitivity test of the patient as shown in Table 2 , A. dhakensis was found to be susceptible to ceftazidime (MIC = 2 μg/ml), cefoperazone/sulbactam (MIC = 16 μg/ml), cefepime (MIC = 0.5 μg/ml), aztreonam (MIC ≤ 1 μg/ml), imipenem (MIC ≤ 0.25 μg/ml), meropenem (MIC ≤ 0.25 μg/ml), amikacin (MIC ≤ 2 μg/ml), ciprofloxacin (MIC ≤ 0.25 μg/ml), levofloxacin (MIC ≤ 0.12 μg/ml), tigecycline (MIC ≤ 0.5 μg/ml), and trimethoprim/sulfamethoxazole (MIC ≤ 20 μg/ml). A. dhakensis was found to be resistant to piperacillin/tazobactam (MIC ≥ 128 μg/ml). The drug resistance genes of the bacteria could not be ascribed to any carbapenemase genes (CphA, KPC, IMP, VIM, NDM, and OXA-48-like), extended-spectrum β-lactamase genes (CTX-M-1, CTX-M-9, CTX-M-15-like, TEM, and SHV), and Ampc enzyme genes (ACC and FOX). The pathogenic bacterial infection was susceptible to imipenem cilastatin sodium. Unfortunately, the patient died due to rapid disease progression.

Table 2. Drug sensitivity test of the patient.

Based on the diagnosis and treatment process of this patient, we realized that Aeromonas is not a common bacterium in doctors’ empirical diagnoses of community-acquired pneumonia patients. First, the pathogenic microorganisms responsible for hemoptysis in community-acquired pneumonia are Staphylococcus aureus , Mycobacterium tuberculosis , Streptococcus pneumoniae , Klebsiella pneumoniae , Aspergillus , and Mucor . Aeromonas , and infection with community-acquired pneumonia as the initial symptom and hemolysis lead to pulmonary hemorrhage, multiple organ dysfunction, and hemorrhagic shock, is rare. Second, the patient was admitted to the hospital with respiratory symptoms rather than the common symptom of diarrhea caused by Aeromonas infection, which is a rare manifestation of Aeromonas infection, and the occurrence of hemolytic uremic syndrome is again a rare clinical symptom. Third, based on the literature review, Aeromonas infection occurs in individuals with low immunity to the disease ( 31 ); however, this patient was young with no history of basic diseases or low immunity situation. In the present case, Aeromonas caused rapid progression, indicating that it could also infect the normal immune population and can also appear in severe manifestations. Fourth, although the patient had a clear manifestation of hemolytic uremic syndrome caused by Aeromonas infection, Escherichia coli is the most common pathogen causing the syndrome, followed by Shigella dysentery, Salmonella , Campylobacter , Yersinia , and enterovirus ( 32 , 33 ). Only two cases of Aeromonas causing hemolytic uremic syndrome have been reported to date ( 33 – 35 ), and hence, the clinical presentation of this patient is rare. Fifth, if the patient was admitted to the hospital when respiratory symptoms occurred, cephalosporins or quinolones were administered according to the experience of doctors in the treatment of community-acquired pneumonia in order to make a life-saving treatment attempt.

Data availability statement

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

Ethics statement

The studies involving humans were approved by the First Affiliated Clinical Research Ethics Review Committee of Chongqing Medical University. The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study. Written informed consent was obtained from the relation for the publication of any potentially identifiable images or data included in this article.

Author contributions

DL: Writing – original draft, Writing – review & editing. LD: Writing – original draft, Writing – review & editing.

The author(s) 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

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

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Keywords : community-acquired pneumonia, hemoptysis, Aeromonas , hemolytic uremic syndrome, multiple organ dysfunction

Citation: Luo D and Dai L (2024) A 26-year-old man with multiple organ failure caused by Aeromonas dhakensis infection: a case report and literature review. Front. Med. 11:1289338. doi: 10.3389/fmed.2024.1289338

Received: 05 September 2023; Accepted: 29 February 2024; Published: 17 April 2024.

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Copyright © 2024 Luo and Dai. 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: Liwan Dai, [email protected]