Intended for healthcare professionals

CCBYNC Open access

Effect of editors’ implementation of CONSORT guidelines on the reporting of abstracts in high impact medical journals: interrupted time series analysis

BMJ 2012; 344 doi: (Published 22 June 2012) Cite this as: BMJ 2012;344:e4178
  1. Sally Hopewell, senior research fellow12,
  2. Philippe Ravaud, professor2345,
  3. Gabriel Baron, statistician234,
  4. Isabelle Boutron, associate professor2345
  1. 1Centre for Statistics in Medicine, University of Oxford, Wolfson College, Oxford OX2 6UD, UK
  2. 2INSERM, U738, Paris, France
  3. 3Assistance Publique des Hôpitaux de Paris, Hôtel Dieu Hospital, Centre of Clinical Epidemiology, Paris
  4. 4University of Paris Descartes, Sorbonne Paris Cité, Faculty of Medicine, Paris
  5. 5French Cochrane Centre, Paris
  1. Correspondence to: S Hopewell sally.hopewell{at}
  • Accepted 17 April 2012


Objective To investigate the effect of the CONSORT for Abstracts guidelines, and different editorial policies used by five leading general medical journals to implement the guidelines, on the reporting quality of abstracts of randomised trials.

Design Interrupted time series analysis.

Sample We randomly selected up to 60 primary reports of randomised trials per journal per year from five high impact, general medical journals in 2006-09, if indexed in PubMed with an electronic abstract. We excluded reports that did not include an electronic abstract, and any secondary trial publications or economic analyses. We classified journals in three categories: those not mentioning the guidelines in their instructions to authors (JAMA and New England Journal of Medicine), those referring to the guidelines in their instructions to authors but with no specific policy to implement them (BMJ), and those referring to the guidelines in their instructions to authors with an active policy to implement them (Annals of Internal Medicine and Lancet). Two authors extracted data independently using the CONSORT for Abstracts checklist.

Main outcome Mean number of CONSORT items reported in selected abstracts, among nine items reported in fewer than 50% of the abstracts published across the five journals in 2006.

Results We assessed 955 reports of abstracts of randomised trials. Journals with an active policy to enforce the guidelines showed an immediate increase in the level of mean number of items reported (increase of 1.50 items; P=0.0037). At 23 months after publication of the guidelines, the mean number of items reported per abstract for the primary outcome was 5.41 of nine items, a 53% increase compared with the expected level estimated on the basis of pre-intervention trends. The change in level or trend did not increase in journals with no policy to enforce the guidelines (BMJ, JAMA, and New England Journal of Medicine).

Conclusion Active implementation of the CONSORT for Abstracts guidelines by journals can lead to improvements in the reporting of abstracts of randomised trials.


  • We thank Cindy Mulrow (Annals of Internal Medicine), Trish Groves (BMJ), and David McNamee (Lancet) for providing an insight into their journal editorial processes, and all those involved in development of the CONSORT for Abstracts guidelines.

  • Contributors: SH and IB were involved in the design, implementation, and analysis of the study; and in writing the final manuscript. PR and GB were involved in the design and analysis of the study, and in commenting on drafts of the final manuscript. SH is responsible for the overall content as guarantor.

  • Funding: This study received no external funding.

  • Competing interests: All authors have completed the Unified Competing Interest form at (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; SH, IB, and PR are members of the CONSORT Group; no other relationships or activities that could appear to have influenced the submitted work.

  • Data sharing: Technical appendix, statistical code, and dataset available from the corresponding author at: sally.hopewell{at}

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: and

View Full Text