Consolidated Standards of Reporting Trials
CONSORT (Consolidated Standards Of Reporting Trials) encompasses various initiatives developed by the CONSORT Group to alleviate the problems arising from inadequate reporting of randomized controlled trials. It is part of the larger EQUATOR Network initiative to enhance the transparency and accuracy of reporting in research.
The CONSORT Statement
The main product of the CONSORT Group is the CONSORT Statement, which is an evidence-based, minimum set of recommendations for reporting randomized trials. It offers a standard way for authors to prepare reports of trial findings, facilitating their complete and transparent reporting, reducing the influence of bias on their results, and aiding their critical appraisal and interpretation.
The most recent version of the Statement—the CONSORT 2010 Statement—consists of a 25-item checklist and a participant flow diagram, along with some brief descriptive text. The checklist items focus on reporting how the trial was designed, analyzed, and interpreted; the flow diagram displays the progress of all participants through the trial. The Statement has been translated into several languages.
The CONSORT "Explanation and Elaboration" document explains and illustrates the principles underlying the CONSORT Statement. It is strongly recommended that it be used in conjunction with the CONSORT Statement.
Considered an evolving document, the CONSORT Statement is subject to periodic changes as new evidence emerges; the most recent update was published in March 2010. The current definitive version of the CONSORT Statement and up-to-date information on extensions are placed on the CONSORT website.
The main CONSORT Statement is based on the "standard" two-group parallel design. Extensions of the CONSORT Statement have been developed to give additional guidance for randomized trials with specific designs (e.g., cluster randomized trials, noninferiority and equivalence trials, pragmatic trials,), data (e.g., harms, abstracts), and interventions (e.g., herbals, non-pharmacologic treatments, acupuncture). This list is, by no means, exhaustive, and work is ongoing.
In 1993, 30 experts - medical journal editors, clinical trialists, epidemiologists, and methodologists - met in Ottawa, Canada to discuss ways of improving the reporting of randomized trials. This meeting resulted in the Standardized Reporting of Trials (SORT) statement, a 32-item checklist and flow diagram in which investigators were encouraged to report on how randomized trials were conducted.
Concurrently, and independently, another group of experts, the Asilomar Working Group on Recommendations for Reporting of Clinical Trials in the Biomedical Literature, convened in California, USA, and were working on a similar mandate. This group also published recommendations for authors reporting randomized trials.
At the suggestion of Dr. Drummond Rennie, from JAMA, in 1995 representatives from both these groups met in Chicago, USA, with the aim of merging the best of the SORT and Asilomar proposals into a single, coherent evidence-based recommendation. This resulted in the Consolidated Standards of Reporting Trials (CONSORT) Statement, which was first published in 1996. Further meetings of the CONSORT Group in 1999 and 2000 led to the publication of the revised CONSORT Statement in 2001.
Since the revision in 2001, the evidence base to inform CONSORT has grown considerably; empirical data highlighting new concerns regarding the reporting of randomized trials. Therefore, a third CONSORT Group meeting was held in 2007, resulting in publication of a newly revised CONSORT Statement and explanatory document in 2010. Users of the guideline are strongly recommended to refer to the most up-to-date version while writing or interpreting reports of clinical trials.
The CONSORT Statement has gained considerable support since its inception in 1996. Over 600 journals and editorial groups worldwide now endorse it, including The Lancet, BMJ, JAMA, New England Journal of Medicine, World Association of Medical Editors, and International Committee of Medical Journal Editors. The 2001 revised Statement has been cited over 1,200 times and the accompanying explanatory document over 500 times. Another indication of CONSORT’s impact is reflected in the approximately 17,500 hits per month that the CONSORT website has received. It has also recently been published as a book for those involved in the planning, conducting and interpretation of clinical trials.
Similar initiatives to improve the reporting of other types of research have arisen after the introduction of CONSORT. They include: Strengthening the Reporting of Observational Studies in Epidemiology (STROBE), Standards for the Reporting of Diagnostic Accuracy Studies (STARD), Strengthening the Reporting of Genetic Association studies (STREGA), Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), Standards for Quality Improvement Reporting Excellence (SQUIRE), among others. These reporting guidelines have been incorporated into the EQUATOR Network initiative to enhance the transparent and accurate reporting of research studies.
- Schulz KF, Altman DG, Moher D; CONSORT Group. CONSORT 2010 statement: updated guidelines for reporting parallel group randomised trials. BMJ. 2010 Mar23;340:c332
- Moher D, Hopewell S, Schulz KF, Montori V, Gøtzsche PC, Devereaux PJ, Elbourne D, Egger M, Altman DG. CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials. BMJ. 2010;340:c869
- Campbell MK, Elbourne DR, Altman DG. CONSORT statement: extension to cluster randomised trials. BMJ 2004; 328(7441):702-708. 
- Piaggio G, Elbourne DR, Altman DG, Pocock SJ, Evans SJW. Reporting of noninferiority and equivalence randomized trials: An extension of the CONSORT statement. JAMA 2006; 295:1152-1160. 
- Zwarenstein M, Treweek S, Gagnier JJ, Altman DG, Tunis S, Haynes B, Oxman AD, Moher D for the CONSORT and Pragmatic Trials in Healthcare (Practihc) group. Improving the reporting of pragmatic trials: an extension of the CONSORT statement. BMJ 2008; 337;a2390. 
- Ioannidis JP, Evans SJ, Gotzsche PC, O'Neill RT, Altman DG, Schulz K, Moher D. Better reporting of harms in randomized trials: an extension of the CONSORT statement. Ann Intern Med 2004; 141(10):781-788. 
- Hopewell S, Clarke M, Moher D, Wager E, Middleton P, Altman DG, Schulz KF and the CONSORT Group. CONSORT for reporting randomized controlled trials in journal and conference abstracts: explanation and elaboration. PLoS Med 2008 5(1): e20. 
- Gagnier JJ, Boon H, Rochon P, Moher D, Barnes J, Bombardier C. Reporting randomized, controlled trials of herbal interventions: an elaborated CONSORT statement. Ann Intern Med 2006; 144(5):364-367. 
- Boutron I, Moher D, Altman DG, Schulz K, Ravaud P, for the CONSORT Group. Extending the CONSORT Statement to randomized trials of nonpharmacologic treatment: explanation and elaboration. Ann Intern Med 2008: 148(4):295-309. 
- MacPherson H, Altman DG, Hammerschlag R, Youping L, Taixiang W, White A, Moher D; STRICTA Revision Group. Revised STandards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA): extending the CONSORT statement. PLoS Med. 2010 Jun 8;7(6):e1000261 
- The Standards of Reporting Trials Group. A proposal for structured reporting of randomized controlled trials. The Standards of Reporting Trials Group. JAMA. 1994; 272(24):1926-1931.
- Working Group on Recommendations for Reporting of Clinical Trials in the Biomedical Literature. Call for comments on a proposal to improve reporting of clinical trials in the biomedical literature. Working Group on Recommendations for Reporting of Clinical Trials in the Biomedical Literature. Ann Intern Med. 1994; 121(11):894-895.
- Rennie D. Reporting randomized controlled trials. An experiment and a call for responses from readers. JAMA 1995; 273(13):1054-1055.
- Begg C, Cho M, Eastwood S, Horton R, Moher D, Olkin I, Pitkin R, Rennie D, Schulz KF, Simel D, Stroup DF. Improving the quality of reporting of randomized controlled trials: the CONSORT statement. JAMA 1996; 276(8):637-639.
- Moher D, Schulz KF, Altman DG. The CONSORT statement: revised recommendations for improving the quality of reports of parallel-group randomized trials . Ann Intern Med 2001; 134(8):657-662. 
- Keech A, Gebski VJ, Pike R. Interpreting and reporting clinical trials. A guide to the CONSORT Statement and the principles of randomised controlled trials. 2007: Australasian Medical Publishing: NSW, Australia.
- Plint AC, Moher D, Morrison A, Schulz K, Altman DG, Hill C, Gaboury I. Does the CONSORT checklist improve the quality of reports of randomised controlled trials? A systematic review. Med J Aust 2006; 185(5):263-267.
- Vandenbroucke JP. The making of STROBE. Epidemiology 2007;18: 797e9.
- Knottnerus JA, Tugwell P. The standards for reporting of diagnostic accuracy. J Clin Epidemiol 2003;56:1118e27
- Little J, Higgins JPT, Ioannidis JPA, Moher D, Gagnon F, Von Elm E, et al. STrengthening the REporting of Genetic Association studies (STREGA)-an extension of the STROBE Statement. J Clin Epidemiol 2009;62:597e608
- Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche P, et al. and the PRISMA Group (2009) The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: Explanation and elaboration. PLoS Med 6: e1000100. doi:10.1371/journal.pmed.1000100
- Davidoff F, Batalden P, Stevens D, Ogrinc G, Mooney S, SQUIRE Development Group. Publication guidelines for improvement studies in health care: evolution of the SQUIRE Project. Ann Intern Med 2008;149:670e6
- Simera I, Altman DG, Moher D, Schulz K, Hoey J. The EQUATOR Network: facilitating transparent and accurate reporting of health research. Serials 2008 Nov 21 (3): 183-87