Write Abstracts, Literature Reviews, and Annotated Bibliographies: Home
- Abstract Guides & Examples
- Literature Reviews
- Annotated Bibliographies & Examples
- Student Research
What is an Abstract?
An abstract is a summary of points (as of a writing) usually presented in skeletal form ; also : something that summarizes or concentrates the essentials of a larger thing or several things. (Merriam-Webster Dictionary Online)
An abstract is a brief summary of a research article, thesis, review, conference proceeding or any in-depth analysis of a particular subject or discipline, and is often used to help the reader quickly ascertain the paper's purpose. When used, an abstract always appears at the beginning of a manuscript, acting as the point-of-entry for any given scientific paper or patent application. Abstraction and indexing services are available for a number of academic disciplines, aimed at compiling a body of literature for that particular subject. (Wikipedia)
An abstract is a brief, comprehensive summary of the contents of an article. It allows readers to survey the contents of an article quickly. Readers often decide on the basis of the abstract whether to read the entire article. A good abstract should be: ACCURATE --it should reflect the purpose and content of the manuscript. COHERENT --write in clear and concise language. Use the active rather than the passive voice (e.g., investigated instead of investigation of). CONCISE --be brief but make each sentence maximally informative, especially the lead sentence. Begin the abstract with the most important points. The abstract should be dense with information. ( Publication Manual of the American Psychological Association)
An abstract of a report of an empirical study should describe: (1) the problem under investigation (2) the participants with specific characteristics such as age, sex, ethnic group (3) essential features of the study method (4) basic findings (5) conclusions and implications or applications. An abstract for a literature review or meta-analysis should describe: (1) the problem or relations under investigation (2) study eligibility criteria (3) types of participants (4) main results, including the most important effect sizes, and any important moderators of these effect sizes (5) conclusions, including limitations (6) implications for theory, policy, and practice. An abstract for a theory-oriented paper should describe (1) how the theory or model works and the principles on which it is based and (2) what phenomena the theory or model accounts for and linkages to empirical results. An abstract for a methodological paper should describe (1) the general class of methods being discussed (2) the essential features of the proposed method (3) the range of application of the proposed method (4) in the case of statistical procedures, some of its essential features such as robustness or power efficiency. An abstract for a case study should describe (1) the subject and relevant characteristics of the individual, group, community, or organization presented (2) the nature of or solution to a problem illustrated by the case example (3) questions raised for additional research or theory.
- What is a Literature Review?
A literature review is a body of text that aims to review the critical points of current knowledge including substantive findings as well as theoretical and methodological contributions to a particular topic. Literature reviews are secondary sources, and as such, do not report any new or original experimental work.Most often associated with academic-oriented literature, such as a thesis, a literature review usually precedes a research proposal and results section. Its ultimate goal is to bring the reader up to date with current literature on a topic and forms the basis for another goal, such as future research that may be needed in the area.A well-structured literature review is characterized by a logical flow of ideas; current and relevant references with consistent, appropriate referencing style; proper use of terminology; and an unbiased and comprehensive view of the previous research on the topic. (Wikipedia)
Literature Review: An extensive search of the information available on a topic which results in a list of references to books, periodicals, and other materials on the topic. ( Online Library Learning Center Glossary )
"... a literature review uses as its database reports of primary or original scholarship, and does not report new primary scholarship itself. The primary reports used in the literature may be verbal, but in the vast majority of cases reports are written documents. The types of scholarship may be empirical, theoretical, critical/analytic, or methodological in nature. Second a literature review seeks to describe, summarize, evaluate, clarify and/or integrate the content of primary reports."
Cooper, H. M. (1988), "The structure of knowledge synthesis", Knowledge in Society , Vol. 1, pp. 104-126
- Literature Review Guide
- Literature Review Tutorial
- Literature Review Defined
- Next: Abstract Guides & Examples >>
- Last Updated: Nov 23, 2023 8:40 AM
- URL: https://library.geneseo.edu/abstracts
Fraser Hall Library | SUNY Geneseo
Fraser Hall 203
Milne Building Renovation Updates
Connect With Us!
Fraser Hall Library is the home of Geneseo Authors Hall, a collection of over 90 years of Geneseo Authors' works.
Fraser Hall Library is the home of KnightScholar Services , which encourages the creation, access, curation, and preservation of scholarly, creative, and cultural works produced by the SUNY Geneseo community.
Fraser Hall Library is the home of the award winning IDS Project , a collaboration of over 100 libraries supporting and enhancing resource sharing.
Writing learning center (wlc).
Fraser Hall 208
How do I Write a Literature Review?: #5 Writing the Review
- Step #1: Choosing a Topic
- Step #2: Finding Information
- Step #3: Evaluating Content
- Step #4: Synthesizing Content
- #5 Writing the Review
- Citing Your Sources
WRITING THE REVIEW
You've done the research and now you're ready to put your findings down on paper. When preparing to write your review, first consider how will you organize your review.
The actual review generally has 5 components:
Abstract - An abstract is a summary of your literature review. It is made up of the following parts:
- A contextual sentence about your motivation behind your research topic
- Your thesis statement
- A descriptive statement about the types of literature used in the review
- Summarize your findings
- Conclusion(s) based upon your findings
Introduction : Like a typical research paper introduction, provide the reader with a quick idea of the topic of the literature review:
- Define or identify the general topic, issue, or area of concern. This provides the reader with context for reviewing the literature.
- Identify related trends in what has already been published about the topic; or conflicts in theory, methodology, evidence, and conclusions; or gaps in research and scholarship; or a single problem or new perspective of immediate interest.
- Establish your reason (point of view) for reviewing the literature; explain the criteria to be used in analyzing and comparing literature and the organization of the review (sequence); and, when necessary, state why certain literature is or is not included (scope) -
Body : The body of a literature review contains your discussion of sources and can be organized in 3 ways-
- Chronological - by publication or by trend
- Thematic - organized around a topic or issue, rather than the progression of time
- Methodical - the focusing factor usually does not have to do with the content of the material. Instead, it focuses on the "methods" of the literature's researcher or writer that you are reviewing
You may also want to include a section on "questions for further research" and discuss what questions the review has sparked about the topic/field or offer suggestions for future studies/examinations that build on your current findings.
Conclusion : In the conclusion, you should:
Conclude your paper by providing your reader with some perspective on the relationship between your literature review's specific topic and how it's related to it's parent discipline, scientific endeavor, or profession.
Bibliography : Since a literature review is composed of pieces of research, it is very important that your correctly cite the literature you are reviewing, both in the reviews body as well as in a bibliography/works cited. To learn more about different citation styles, visit the " Citing Your Sources " tab.
- Writing a Literature Review: Wesleyan University
- Literature Review: Edith Cowan University
- << Previous: Step #4: Synthesizing Content
- Next: Citing Your Sources >>
- Last Updated: Aug 22, 2023 1:35 PM
- URL: https://libguides.eastern.edu/literature_reviews
About the Library
- Collection Development
- Circulation Policies
- Mission Statement
- Staff Directory
Using the Library
- A to Z Journal List
- Library Catalog
- Research Guides
- Research Help
Warner Memorial Library
An official website of the United States government
The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
- Account settings
- Advanced Search
- Journal List
- Bull Med Libr Assoc
- v.88(4); 2000 Oct
Clarifying the abstracts of systematic literature reviews *
1 Department of Psychology Keele University Staffordshire United Kingdom
2 † Author's address for correspondence: James Hartley, B.A., Ph.D., Department of Psychology, Keele University, Staffordshire, ST5 5BG, United Kingdom; email, [email protected]
Background: There is a small body of research on improving the clarity of abstracts in general that is relevant to improving the clarity of abstracts of systematic reviews.
Objectives: To summarize this earlier research and indicate its implications for writing the abstracts of systematic reviews.
Method: Literature review with commentary on three main features affecting the clarity of abstracts: their language, structure, and typographical presentation.
Conclusions: The abstracts of systematic reviews should be easier to read than the abstracts of medical research articles, as they are targeted at a wider audience. The aims, methods, results, and conclusions of systematic reviews need to be presented in a consistent way to help search and retrieval. The typographic detailing of the abstracts (type-sizes, spacing, and weights) should be planned to help, rather than confuse, the reader.
Several books and review papers have been published over the last twenty-five years about improving the clarity of the abstracts of articles in scientific journals, including several recent studies [ 1–5 ]. Three main areas of importance have been discussed:
- the language, or the readability, of an abstract;
- the sequence of information, or the structure, of an abstract; and
- the typography, or the presentation, of an abstract.
This paper considers the implications of the findings from research in each of these overlapping areas to the more specific area of writing abstracts for what are called “systematic reviews.” Such reviews in medical journals typically use standard procedures for assessing the evidence obtained from separate studies for and against the effectiveness of a particular treatment. The term “systematic” implies that the authors have used a standard approach to minimizing biases and random errors and that the methods chosen for the approach will be documented in the materials and methods sections of the review. Examples of such reviews may be found in Chalmers's and Altman's text [ 6 ] and in papers published in medical journals, particularly Evidence-Based Medicine. Figure 1 provides a fictitious example of an abstract for such a paper.
“Before” and “after” examples designed to show how differences in typography and wording can enhance the clarity of an abstract. Abstract courtesy of Philippa Middleton.
THE LANGUAGE OF THE TEXT
Research on the readability of conventional journal abstracts suggests that they are not easy to read. Studies in this area typically use the Flesch Reading Ease (R.E.) scores as their measure of text difficulty [ 7 ]. This measure, developed in the 1940s, is based upon the somewhat over simple idea that the difficulty of text is a function of the length of the sentences in the text and the length of the words within these sentences. The original Flesch formula is that R.E. = 206.835 − 0.846w − 1.015s (where w = the average number of syllables in 100 words and s = the average number of words per sentence). The scores normally range from 0 to 100, and the lower the score the more difficult the text is to read; Table 1 gives typical examples. Today, Flesch R.E. scores accompany most computerized spell checkers, and this removes the difficulties of hand calculation; although different programs give slightly different results [ 8, 9 ].
Table 1 The interpretation of Flesch scores
Table 2 summarizes the Flesch scores obtained for numerous journal abstracts in seven studies. The low scores shown here support the notion that journal abstracts are difficult to read. With medical journals, in particular, this difficulty may stem partly from complex medical terminology. Readability scores such as these are widely quoted, even though there is considerable debate about their validity, largely because they ignore the readers' prior knowledge and motivation [ 10, 11 ].
Table 2 Flesch Reading Ease scores reported in previous research on abstracts in journal articles
A second cause of difficulty in understanding text is that, although the wording may be simple and the sentences short, the concepts being described may not be understood by the reader. Thus, for example, although the sentence “God is grace” is extremely readable (in terms of the Flesch), it is not easy to explain what it actually means! In systematic reviews, to be more specific, the statistical concepts of the confidence interval and the adjusted odds ratio ( Figure 1 ) may be well understood by medical researchers, but they will not be understood by all readers.
A third cause of difficulty in prose lies in the scientific nature of the text that emphasizes the use of the third person, together with the passive rather than the active tense. Graetz writes of journal abstracts:
The abstract is characterized by the use of the past tense, the third person, passive, and the non-use of negatives…. It is written in tightly worded sentences, which avoid repetition, meaningless expressions, superlatives, adjectives, illustrations, preliminaries, descriptive details, examples, footnotes. In short it eliminates the redundancy which the skilled reader counts on finding in written language and which usually facilitates comprehension. [ 12 ]
In systematic reviews, it is easy to find sentences like “Trial eligibility and quality were assessed” that would be more readable if they were written as “We assessed the eligibility and the quality of the trials.” Furthermore, there are often short telegrammatic communications, some of which contain no verbs. Figure 1 provides an example (under the subheading “Selection criteria”).
There are, of course, numerous guidelines on how to write clear abstracts and more readable medical text [ 13–16 ] but, at present, there are few such guidelines for writing the abstracts of systematic reviews. Mulrow, Thacker, and Pugh [ 17 ] provide an excellent early example, and there are now regularly updated guidelines in the Cochrane Handbook [ 18 ].
Nonetheless, even when such guidelines are followed, evaluating the clarity of medical text is not easy. But some methods of doing so may be adapted from the more traditional literature on text evaluation. Schriver, for example, describes three different methods of text evaluation—text-based, expert-based, and reader-based methods [ 19 ]:
- Text-based methods are ones that can be used without recourse to experts or to readers. Such methods include computer-based readability formulae (such as the Flesch measure described above) and computer-based measures of style and grammar.
- Expert-based methods are ones that use experts to make assessments of the effectiveness of a piece of text. Medical experts may be asked, for example, to judge the suitability of the information contained in a patient information leaflet.
- Reader-based methods are ones that involve actual readers in making assessments of the suitability of the text, for themselves and for others. Patients, for example, may be asked to comment on medical leaflets or be tested on how much they can recall from them.
Although all three methods of evaluation are useful, especially in combination, this writer particularly recommends reader-based methods for evaluating the readability of abstracts in systematic reviews. This recommendation is because the readers of such systematic reviews are likely to be quite disparate in their aims, needs, and even in the languages that they speak. As the 1999 Cochrane Handbook put it:
Abstracts should be made as readable as possible without compromising scientific integrity. They should primarily be targeted to health care decision makers (clinicians, consumers, and policy makers) rather than just researchers. Terminology should be reasonably comprehensible to a general rather than a specialist medical audience [emphasis added]. [ 20 ]
Expert-based measures on their own may be misleading. For instance, there is evidence to suggest that the concerns of professionals are different from those of other personnel [ 21 ]. Wilson et al. [ 22 ], for instance, report wide differences between the responses of general practitioners (GPs) and patients in the United Kingdom in responses to questions concerning the content and usefulness of several patient information leaflets. Table 3 shows some of their replies.
Table 3 Differences between general practitioners (GPs) and patients in their views about particular patient information leaflets
THE STRUCTURE OF THE TEXT
In recent times, particularly in the medical field, there has been great interest in the use of so-called “structured abstracts”—abstracts that typically contain subheadings, such as “background,” “aims,” “methods,” “results,” and “conclusions.” Indeed, the early rise in the use of such abstracts was phenomenal [ 23 ], and it has no doubt continued to be so up to the present day. Evaluation studies have shown that structured abstracts are more effective than traditional ones, particularly in the sense that they contain more information [ 24–31 ]. However, a caveat here is that some authors still omit important information, and some still include information in the abstract that does not match exactly what is said in the article [ 32–35 ].
Additional research has shown that structured abstracts are sometimes easier to read and to search than are traditional ones [ 36, 37 ], but others have questioned this conclusion [ 38, 39 ]. Nonetheless, in general, both authors and readers apparently prefer structured to traditional abstracts [ 40–42 ]. The main features of structured abstracts that lead to these findings are that:
- the texts are opened-up and clearly subdivided into their component parts, which helps the reader perceive their structure;
- the abstracts sequence their information in a consistent order under consistent subheadings, which facilitates search and retrieval; and
- the writing under these subheadings ensures that authors do not miss out anything important.
Nonetheless, there are some difficulties—and these difficulties become more apparent after considering the structured abstracts of systematic reviews. First of all, the typographic practice of denoting the subheadings varies from journal to journal [ 43, 44 ]. Second, and of more relevance here, there is a range of subheadings used both within and among journals [ 45, 46 ], which militates against rapid retrieval. Table 4 shows an example of these variations by listing the subheadings used in the abstracts in just one volume of the Journal of the American Medical Association. Finally, it appears that some authors omit important subheadings or present them in a different order (e.g., reporting the conclusions before the results) [ 47 ].
Table 4 Different numbers of subheadings used in abstracts in the same volume of the Journal of the American Medical Association
The implications of these difficulties are that a decision needs to be made, based upon appropriate evaluation studies, about what are the key subheadings that can be used consistently in systematic reviews. The journal Evidence-Based Medicine, for example, uses the following six subheadings: “Question(s),” “Data sources,” “Study selection,” “Data extraction,” “Main results,” and “Conclusions,” but the Cochrane Handbook [ 48 ] recommends another seven: “Background,” “Objectives,” “Search strategy,” “Selection criteria,” “Data collection and analysis,” “Main results,” and “Reviewers' conclusions.” Presumably, these different sets of subheadings have developed over time with experience. For example, “Objective(s)” initially preceded “Question(s)” in Evidence-Based Medicine. In the future, refining these subheadings further may be possible by using appropriate typographic cueing, to separate important from minor subheadings, such as those headings used in the Journal of the American Medical Association. It will be essential, however, to use consistent terminology throughout the literature to aid both the creation of and retrieval from the abstracts of systematic reviews. Editors may consult their readers and their authors for possible solutions to this problem.
THE TYPOGRAPHIC SETTING FOR ABSTRACTS OF SYSTEMATIC REVIEWS
Early research on the typographic setting of structured abstracts in scientific articles suggests that the subheadings should be printed in bold capital letters with a line space above each subheading [ 49 ]. But this research has been done with structured abstracts that only have four subheadings. However, the abstracts of systematic reviews are likely to have more than four-subheadings—indeed, as noted above, six or seven seem typical. Also, some of these subheadings may be more important than others.
Generally speaking, there are two ways of clarifying the structure in typography. One is to vary the typography, the other to vary the spacing [ 50, 51 ]. In terms of typography, not overdoing is best; there is no need to use two cues when one will do. Thus, it may be appropriate to use bold lettering for the main subheadings and italic lettering for the less important ones, without adding the additional cues of capital letters or underlining. Also, as the subheadings appear as the first word on a line, placing a line space above them enhances their effectiveness, so there is no need to indent the subheadings as well. The abstracts published in the Cochrane Library follow this procedure.
Finally in this section, it should be noted that it is easier to read an abstract:
- that is set in the same type-size (or larger) than the body of the text of the review, unlike many journal abstracts, [ 52 ];
- that does not use “fancy'” typography or indeed bold or italic for its substantive text [ 53 ]; and
- that is set in “unjustified text,” with equal word spacing and a ragged right-hand margin, rather than in “justified text,” with unequal word spacing and straight left- and right-hand margins. This is particularly the case if the abstract is being read on screen [ 54 ].
The research reviewed above suggests that, in presenting the abstracts to systematic reviews, attention needs to be paid to their language, their structure, and their typographic design. Figure 1 shows a “before and after” example for a fictitious abstract for a systematic review. The purpose of this example is to encapsulate the argument of this paper and to show how changes in wording and typography can enhance the clarity of an abstract for a systematic review.
The author is indebted to Iain Chalmers, Philippa Middleton, Mark Starr, and anonymous referees for assistance in the preparation of this paper.
* Based on invited presentation at the VIIth Cochrane Colloquium, Rome, Italy, October 1999.
- Berkenkotter C, Huckin TN. Genre knowledge in disciplinary communication . Hillsdale, NJ: Erlbaum. 1995 [ Google Scholar ]
- Hartley J. Three ways to improve the clarity of journal abstracts . Brit J Educ Psychol . 1994 Jun. 64 ( 2 ):331–43. [ Google Scholar ]
- Swales JM. Genre analysis: English in academic and research settings . Cambridge, U.K.: Cambridge University Press. 1990 [ Google Scholar ]
- Swales JM, Feak C. Academic writing for graduate students . Michigan: University of Michigan Press. 1994 [ Google Scholar ]
- Anonymous. A proposal for more informative abstracts in clinical articles. Ad Hoc Working Group for Critical Appraisal of the Medical Literature . Ann Intern Med . 1987 Apr. 106 ( 4 ):598–604. [ PubMed ] [ Google Scholar ]
- Chalmers I, Altman DG. eds. . Systematic reviews . London, U.K.: British Medical Journal Publishing Group. 1995 [ Google Scholar ]
- Flesch R. A new readability yardstick . J Appl Psychol . 1948 Jun. 32 :221–3. [ PubMed ] [ Google Scholar ]
- Mailloux SL, Johnson ME, Fisher DG, and Pettibone TJ. How reliable is computerized assessment of readability? Computers and Nursing . 1995 Sep–Oct. 13 ( 5 ):221–5. [ PubMed ] [ Google Scholar ]
- Sydes M, Hartley J. A thorn in the Flesch: observations on the unreliability of computer-based readability formulae . British Journal of Educational Technology . 1997 Apr. 28 ( 2 ):143–5. [ Google Scholar ]
- Davison A, Green G. eds. . Linguistic complexity and text comprehension: readability issues reconsidered . Hillsdale, NJ: Erlbaum. 1988 [ Google Scholar ]
- Hartley J. Designing instructional text . 3d ed. East Brunswick, NJ: Nichols. 1994 [ Google Scholar ]
- Graetz N. Teaching EFL students to extract structural information from abstracts . In: Ulijn JM, Pugh AK, eds. Reading for professional purposes. Leuven, Belgium: ACCO. 1985 125. [ Google Scholar ]
- National Information Standards Organization. An American national standard: guidelines for abstracts . Bethesda, MD: NISO Press. 1997 [ Google Scholar ]
- Hall GM. How to write a paper . London, U.K.: BMJ Pub Group. 1994 [ Google Scholar ]
- Hartley J. What does it say? text design, medical information and older readers . In Park DC, Morrell RW, Shifren K, eds. Processing of medical information in aging patients. Mahwah, NJ: Erlbaum. 1999 233–47. [ Google Scholar ]
- Matthews JR. Successful scientific writing: a step-by-step guide for biological and medical scientists . 2d ed. New York, NY: Cambridge University Press. 2000 [ Google Scholar ]
- Mulrow CD, Thacker SB, and Pugh JA. A proposal for more informative abstracts of review articles . Ann Intern Med . 1988 Apr: 108 ( 4 ):613–5. [ PubMed ] [ Google Scholar ]
- Clarke M, Oxman AD. eds. . Cochrane reviewers' handbook 4.0 [updated July 1999] . In: The Cochrane Library, issue 2 [database on CDROM]. The Cochrane Collaboration. Oxford, U.K.: Update Software. 2000 [ Google Scholar ]
- Schriver KA. Evaluating text quality: the continuum from text-focused to reader-focused methods . IEEE Trans Prof Comm . 1989 Dec. 32 ( 4 ):238–55. [ Google Scholar ]
- Berry DC, Michas IC, Gillie T, and Forster M. What do patients want to know about their medicines, and what do doctors want to tell them? a comparative study . Psychol and Health . 1997. 12 ( 4 ):467–80. [ Google Scholar ]
- Wilson R, Kenny T, Clark J, Moseley D, Newton L, Newton D, and Purves I. Ensuring the readability and efficacy of patient information leaflets . Newcastle, U.K.: Sowerby Health Centre for Health Informatics, Newcastle University. Prodigy Publication. 1998 no. 30. [ Google Scholar ]
- Harbourt AM, Knecht LS, and Humphreys BL. Structured abstracts in MEDLINE 1989–91 . Bull Med Libr Assoc . 1995 Apr. 83 ( 2 ):190–5. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Hartley J. Applying ergonomics to Applied Ergonomics: using structured abstracts . Appl Ergonom . 1999 Dec. 30 ( 6 ):535–41. [ PubMed ] [ Google Scholar ]
- Hartley J, Benjamin M. An evaluation of structured abstracts in journals published by the British Psychological Society . Brit J Educ Psychol . 1998 Sep. 68 ( 3 ):443–56. [ Google Scholar ]
- Haynes RB. More informative abstracts: current status and evaluation . J Clin Epidemiol . 1993 Jul. 46 ( 7 ):595–7. [ PubMed ] [ Google Scholar ]
- McIntosh N, Duc G, and Sedin G. Structure improves content and peer review of abstracts submitted to scientific meetings . European Science Editing . 1999 Jun. 25 ( 2 ):43–7. [ Google Scholar ]
- Scherer RW, Crawley B. Reporting of randomized clinical trial descriptors and the use of structured abstracts . JAMA . 1998 July 15. 280 ( 3 ):269–72. [ PubMed ] [ Google Scholar ]
- Taddio A, Pain T, Fassos FF, Boon H, Ilersich AL, and Einarson TR. Quality of nonstructured and structured abstracts of original research articles in the British Medical Journal, the Canadian Medical Association Journal and the Journal of the American Medical Association . Can Med Assoc J . 1994 May 15. 150 ( 10 ):1611–5. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Tenopir C, Jacso P. Quality of abstracts . Online . 1993 May. 17 ( 3 ):44–55. [ Google Scholar ]
- Froom P, Froom J. Deficiencies in structured medical abstracts . J Clin Epidemiol . 1993 Jul. 46 ( 7 ):591–4. [ PubMed ] [ Google Scholar ]
- Pitkin RM, Branagan MA. Can the accuracy of abstracts be improved by providing specific instructions? a randomized controlled trial . JAMA . 1998 Jul 15. 280 ( 3 ):267–9. [ PubMed ] [ Google Scholar ]
- Pitkin RM, Branagan MA, and Burmeister L. Accuracy of data in abstracts of published research articles . JAMA . 1999 Mar 24–31. 281 ( 12 ):1110–1. [ PubMed ] [ Google Scholar ]
- Hartley J.. Are structured abstracts more/less accurate than traditional ones? a study in the psychological literature. Journal of Information Science. 2000; 26 (4) [ Google Scholar ]
- Hartley J, Sydes M.. Are structured abstracts easier to read than traditional ones? J Res Reading. 1997; 20 (2):122–36. [ Google Scholar ]
- Hartley J, Sydes M, Blurton A.. Obtaining information accurately and quickly: are structured abstracts more efficient? J Info Sc. 1996; 22 (5):349–56. [ Google Scholar ]
- Booth A, O'Rourke AJ.. The value of structured abstracts in information retrieval from MEDLINE. Health Libr Rev. 1997; 14 (3):157–66. [ Google Scholar ]
- O'Rourke AJ. Structured abstracts in information retrieval from biomedical databases: a literature survey . Health Informatics J . 1997 Jan. 3 ( 1 ):17–20. [ Google Scholar ]
- Hartley J, Sydes M.. Which layout do you prefer? an analysis of readers' preferences for different typographic layouts of structured abstracts. J Info Sci. 1996; 22 (1):27–37. [ Google Scholar ]
- Hartley J. Typographic settings for structured abstracts . J Technical Writing and Communication . 2001 in press. [ Google Scholar ]
- Dronberger GB, Kowitz GT.. Abstract readability as a factor in information systems. J Am Soc Inf Sci. 1975; 26 :108–11. [ Google Scholar ]
- Roberts JC, Fletcher CH, and Fletcher SW. Effects of peer review and editing on the readability of articles published in Annals of Internal Medicine . JAMA . 1994 Jul 13. 272 ( 2 ):119–21. [ PubMed ] [ Google Scholar ]
11.8 Writing an abstract
All full reviews must include an abstract of not more than 400 words. The abstract should be kept as brief as possible without sacrificing important content. Abstracts to Cochrane reviews are published in MEDLINE and the Science Citation Index, and are made freely available on the internet. It is therefore important that they can be read as stand-alone documents.
The abstract should summarize the key methods, results and conclusions of the review and should not contain any information that is not in the review. Links to other parts of the review (such as references, studies, tables and figures) may not be included in the abstract. A hypothetical example of an abstract is included in Box 11.8.a .
Abstracts should be targeted primarily at healthcare decision makers (clinicians, informed consumers and policy makers) rather than just to researchers. Terminology should be reasonably comprehensible to a general rather than a specialist healthcare audience. Abbreviations should be avoided, except where they are widely understood (for example, HIV). Where essential, other abbreviations should be spelt out (with the abbreviations in brackets) on first use. Names of drugs and interventions that can be understood internationally should be used wherever possible. Trade names should not be used.
The content under each heading in the abstract should be as follows:
Background: This should be one or two sentences to explain the context or elaborate on the purpose and rationale of the review. If this version of the review is an update of an earlier one, it is helpful to include a sentence such as “This is an update of a Cochrane review first published in YEAR, and previously updated in YEAR”.
Objectives: This should be a precise statement of the primary objective of the review, ideally in a single sentence, matching the Objectives in the main text of the review. Where possible the style should be of the form “To assess the effects of [intervention or comparison] for [health problem] for/in [types of people, disease or problem and setting if specified]”.
Search methods: This should list the sources and the dates of the last search, for each source, using the active form ‘We searched….’ or, if there is only one author, the passive form can be used, for example, ‘Database X, Y, Z were searched’. Search terms should not be listed here. If the CRG’s Specialized Register was used, this should be listed first in the form ‘Cochrane X Group Specialized Register’. The order for listing other databases should be the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, other databases. The date range of the search for each database should be given. For the Cochrane Central Register of Controlled Trials this should be in the form ‘Cochrane Central Register of Controlled Trials ( The Cochrane Library 2007, Issue 1)’. For most other databases, such as MEDLINE, it should be in the form ‘MEDLINE (January 1966 to December 2006)’. Searching of bibliographies for relevant citations can be covered in a generic phrase ‘reference lists of articles’. If there were any constraints based on language or publication status, these should be listed. If individuals or organizations were contacted to locate studies this should be noted and it is preferable to use ‘We contacted pharmaceutical companies’ rather than a listing of all the pharmaceutical companies contacted. If journals were specifically handsearched for the review, this should be noted but handsearching to help build the Specialized Register of the CRG should not be listed.
Selection criteria: These should be given as ‘ [type of study] of [type of intervention or comparison] in [disease, problem or type of people]‘ . Outcomes should only be listed here if the review was restricted to specific outcomes.
Data collection and analysis: This should be restricted to how data were extracted and assessed, and not include details of what data were extracted. This section should cover whether data extraction and assessments of risk of bias were done by more than one person. If the authors contacted investigators to obtain missing information, this should be noted here. What steps, if any, were taken to identify adverse effects should be noted.
Main results: This section should begin with the total number of studies and participants included in the review, and brief details pertinent to the interpretation of the results (for example, the risk of bias in the studies overall or a comment on the comparability of the studies, if appropriate). It should address the primary objective and be restricted to the main qualitative and quantitative results (generally including not more than six key results). The outcomes included should be selected on the basis of which are most likely to help someone making a decision about whether or not to use a particular intervention. Adverse effects should be included if these are covered in the review. If necessary, the number of studies and participants contributing to the separate outcomes should be noted, along with concerns over quality of evidence specific to these outcomes. The results should be expressed narratively as well as quantitatively if the numerical results are not clear or intuitive (such as those from a standardized mean differences analysis). The summary statistics in the abstract should be the same as those selected as the defaults for the review, and should be presented in a standard way, such as ‘odds ratio 2.31 (95% confidence interval 1.13 to 3.45)’. Ideally, risks of events (percentage) or averages (for continuous data) should be reported for both comparison groups. If overall results are not calculated in the review, a qualitative assessment or a description of the range and pattern of the results can be given. However, ‘vote counts’ in which the numbers of ‘positive’ and ‘negative’ studies are reported should be avoided.
Authors’ conclusions: The primary purpose of the review should be to present information, rather than to offer advice or recommendations. The Authors’ conclusions should be succinct and drawn directly from the findings of the review so that they directly and obviously reflect the main results. Assumptions should generally not be made about practice circumstances, values, preferences, tradeoffs; and the giving of advice or recommendations should generally be avoided. Any important limitations of data and analyses should be noted. Important conclusions about the implications for research should be included if these are not obvious.
- Monash Online
Student Academic Success
- 1:1 Consultation 1:1 Consultation
- Study better Study better
- Build digital capabilities Build digital capabilities
- Understand assessments Understand assessments
- Excel at writing Excel at writing
- Enhance your thinking Enhance your thinking
- Present confidently Present confidently
- Collaborate with others Collaborate with others
- Improve your academic English Improve your academic English
- Maintain academic integrity Maintain academic integrity
- Advance your graduate studies Advance your graduate studies
- Workshops Workshops
- Feedback studio Feedback studio
- About us About us
- Skip to content
- Skip to navigation
Structuring a literature review
In general, literature reviews are structured in a similar way to a standard essay, with an introduction, a body and a conclusion. These are key structural elements. Additionally, a stand-alone extended literature review has an abstract. Throughout, headings and subheadings are used to divide up the literature review into meaningful sections.
There is no single “correct” structure for how to structure the content of your literature review – every review is shaped by the nature of the field being reviewed and the specific argument the review is supporting. Here are some common literature review organising patterns:
- historical development (chronological)
- pros and cons
- methodological issues
- key works of a single author
- key works in a particular field of study
For example, a literature review on the definitions of key terms or concepts in a particular field of study might analyse a variety of definitions and conclude by defending a selected definition.
Some of the organising patterns listed above may be used in combination.
Structure a lit review accordion
If you are writing a stand-alone extended literature review, you are required to provide an abstract. The purpose of an abstract is to provide potential readers with an overview of the review content, so that they can determine if it is relevant to their research. The abstract should include brief background information, including any knowledge gaps or discrepancies that the review aims to address, as well as a statement regarding the purpose and scope of the review. A complete abstract also includes a brief statement of the main findings and how they relate to the broader context. The example abstract below includes these elements.
Not all introductions follow exactly the same order. However, there are some key points to include in the introduction to provide your reader with the context and purpose of your review. The general guidelines for the structure of a literature review introduction are:
- Start with a broad introduction to the topic. Include relevant background information and definitions or explanations of the main terms and concepts.
- Provide information that is relevant for your specific topic, and explain the importance of your topic (e.g. why it’s worth reading your literature review).
- Tell the reader what the scope of your review is (e.g. what key points you will include in the body of your review).
- Tell your reader what the aim or purpose of your review is. This is often included at the end of the introduction.
The body of the review contains your review of the literature relevant to your research question or aim. You should structure the body of your literature review in a logical and coherent way. Consider what your sub-topics or sections will be in order to answer your research question thoroughly and coherently. Then consider the most logical order to discuss your sections. Creating sub-headings for the sections of your review will assist you in creating a logical structure and keep you focused on sub-topics relevant to your research aim.
In the body of your literature review, it is important to analyse the literature rather than to merely describe the findings of a number of different literature sources. Some description of the key findings is important to give the reader context. However, your review should also include an analysis of the key themes, gaps in understanding, and points of disagreement between the different literature sources.
There are numerous ways to organise your body paragraphs, depending on your topic. You may want to organise some of your paragraphs:
- in chronological order, e.g. historical findings, more recent findings, current research
- group your literature sources into paragraphs based on similar arguments or findings
- categorise your sources into similar sub-topics and compare different findings within a single paragraph.
Remember to include accurate and relevant citations and references throughout this section.
The assignment excerpt below is an example of how to group similar findings together.
Body paragraph example 1
Another method of organising your body paragraphs is to group papers together that have found different or contradictory results related to the same topic. This helps you to demonstrate your understanding of the literature and highlights the inconsistencies between findings. The assignment body paragraph below is an example of how this can be done.
Body paragraph example 2
Conclude by demonstrating how you have answered your research question and/or how you have achieved your research aim. This tells the audience you have achieved what you intended. Then highlight the key points you discussed. Now you can refer to implications of this knowledge in a broader sense, as well as recommendations for future studies/research (if applicable). The conclusion starts specific and finishes broad.
There are several conventions to note when you are writing your conclusion:
- Don’t include new information in your conclusion. Instead, highlight the key points raised in the earlier sections of your literature review.
- Don’t include in-text citations in your conclusion. This relates to the point above in regards to not including new information.
The example below demonstrates the structural elements of a conclusion.
Check your understanding view.