OPEN ACCESS Freely available online ④PLOS|MEDICINE Guidelines and Guidance PRISMA for Abstracts:Reporting Systematic Reviews in Journal and Conference Abstracts Elaine M.Beller,Paul P.Glasziou,Douglas G.Altman,Sally H Peter C. ewell2,Hilda Bastian, tzsche",Toby Lasserson,David Tovey,for the PRISMA for Abstracts Group Centre.Cope Editoral Unit,London United,France Introduction omplete information,and facilitate the finding of ructured abstracts,studies of the qualit f chnical tral mprove n of an ted iation could not b matic re ew should be to dings dese dings i nine whether reading the full text is osely linked toco atic r ome read rs cannot the full paper,such that ab PRISM to develop ar matic reviews We aso stood by the ss to an a tra Methods for Development of the Checklist published b We established a steering committee (EMB,PPG,SH,DGA).Ir of the the checklist of essential i ems that authors she d consider wh clicks age num ces of gu ance and nd will be )p nted about 25 r full te likely to sta and end with Dephi method [and reduce the [3],but the the PP.Altman DG.Ho cful for studytyT 9201 s and setti aiCtppon ers and revi 6 ed (n)by the ntram yearsgo 61. AbreviationePpcospartdipantihntenvemtionscomparatos,outicomes.nd section advice on onducting and Guidelines and Guidance PRISMA for Abstracts: Reporting Systematic Reviews in Journal and Conference Abstracts Elaine M. Beller1 *, Paul P. Glasziou1 , Douglas G. Altman2 , Sally Hopewell2,7, Hilda Bastian3 , Iain Chalmers4 , Peter C. Gøtzsche5 , Toby Lasserson6 , David Tovey6 , for the PRISMA for Abstracts Group" 1 Centre for Research in Evidence-Based Practice, Bond University, Gold Coast, Australia, 2 Centre for Statistics in Medicine, University of Oxford, Oxford, United Kingdom, 3 National Center for Biotechnology Information, National Library of Medicine, Washington DC, United States of America, 4 James Lind Initiative, Oxford, United Kingdom, 5 Nordic Cochrane Centre, Copenhagen, Denmark, 6 Cochrane Editorial Unit, London, United Kingdom, 7 INSERM, Paris, France Introduction When readers screen the title of an article, and parts of its abstract, they try to determine whether or not to devote their scarce time to reading on. Some may be screening literature to identify the articles that are systematic reviews. Thus, the main function of an abstract of a systematic review should be to signal its systematic methodology. For most readers, the findings described in the abstract will also be key, either as the sole part of an article that will be read, or to determine whether reading the full text is required. Abstracts of systematic reviews are very important, as some readers cannot access the full paper, such that abstracts may be the only option for gleaning research results. This can be because of a pay wall, low Internet download capacity, or if the full article is only available in a language not understood by the reader. Readers in countries where English is not the primary language may have access to an abstract translated to their own language, but not to a translated full text. Conversely, a large proportion of systematic reviews are published by health technology agencies in non-English speaking countries [1], many of which provide only the abstract in English. The predominance of the abstract in biomedical literature use is clear. Within queries to PubMed, most readers look only at titles; only half of searches result in any clicks on content [2]. The average number of titles clicked on to obtain the abstract or full text, even after retrieving several searches in a row, is less than five. Of those clicks, abstracts will be represented about 2.5 times more often than full texts of articles [2]. Even people going straight to a PDF or full text are likely to start, and perhaps end, with reading the abstract. The frequency of viewing full texts is somewhat higher among people searching the Cochrane Database of Systematic Reviews [3], but the same pattern is clear. After the title, the abstract is the most read part of a biomedical article. Abstracts can be useful for screening by study type [4]; facilitating quick assessment of validity [4,5]; enabling efficient perusal of electronic search results [4,6]; clarifying to which patients and settings the results apply [4,5]; providing readers and peer reviewers with explicit summaries of results [5]; facilitating the pre-publication peer review process [7]; and increasing precision of computerised searches [6,7]. Structured abstracts were introduced in the medical literature about 25 years ago [4–6]. They provide readers with a series of headings, generally about the purpose, methods, results, and conclusions of the report, and have been adopted by many journals and conferences. They act as a prompt to the writer to give more complete information, and facilitate the finding of information by the reader. Despite the adoption of structured abstracts, studies of the quality of abstracts of clinical trials have demonstrated that improvement is needed [8,9], and a study of systematic review abstracts demon￾strated that the direction of the effect or association could not be determined in one in four abstracts from the general and specialty medical literature [10]. The PRISMA Statement [11] gives some guidance for abstracts, closely linked to commonly used headings in structured abstracts. After observing that the quality of abstracts of systematic reviews is still poor [10], we decided to develop an extension to the PRISMA Statement to provide guidance on writing abstracts for systematic reviews. We also wanted to provide a checklist enabling the items suggested to fit into any set of headings mandated by a journal or conference submission. Methods for Development of the Checklist We established a steering committee (EMB, PPG, SH, DGA). In collaboration with the steering group of the PRISMA Statement [11], we used the Statement to inform our selection of potential items for the checklist of essential items that authors should consider when reporting the primary results of a systematic review in a journal or conference abstract. The committee generated a list of items from PRISMA and other sources of guidance and information on structured abstracts and abstract composition and reporting [7,11,12], which were found using a thorough search of the literature. In preparation for a consensus meeting, we used a modified Delphi consensus survey method [13] to select and reduce the The Guidelines and Guidance section contains advice on conducting and reporting medical research. Citation: Beller EM, Glasziou PP, Altman DG, Hopewell S, Bastian H, et al. (2013) PRISMA for Abstracts: Reporting Systematic Reviews in Journal and Conference Abstracts. PLoS Med 10(4): e1001419. doi:10.1371/journal.pmed.1001419 Published April 9, 2013 This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Funding: This research was supported (in part) by the Intramural Research Program of the NIH, National Center for Biotechnology Information (National Library of Medicine). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: TL is employed by The Cochrane Collaboration. TL is an editor (unpaid) for the Cochrane Airways Group. The authors have declared that no other competing interests exist. Abbreviations: PICOS, participants, interventions, comparators, outcomes, and study designs. * E-mail: ebeller@bond.edu.au Provenance: Not commissioned; externally peer reviewed. " Membership of the PRISMA for Abstracts Group is provided in the Acknowledgments. PLOS Medicine | www.plosmedicine.org 1 April 2013 | Volume 10 | Issue 4 | e1001419