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. 2010 Mar 23:340:c723.
doi: 10.1136/bmj.c723.

The quality of reports of randomised trials in 2000 and 2006: comparative study of articles indexed in PubMed

Sally Hopewell  1 , Susan Dutton, Ly-Mee Yu, An-Wen Chan, Douglas G Altman
Affiliations

The quality of reports of randomised trials in 2000 and 2006: comparative study of articles indexed in PubMed

Sally Hopewell et al. BMJ. .

Abstract

Objectives: To examine the reporting characteristics and methodological details of randomised trials indexed in PubMed in 2000 and 2006 and assess whether the quality of reporting has improved after publication of the Consolidated Standards of Reporting Trials (CONSORT) Statement in 2001.

Design: Comparison of two cross sectional investigations. Study sample All primary reports of randomised trials indexed in PubMed in December 2000 (n=519) and December 2006 (n=616), including parallel group, crossover, cluster, factorial, and split body study designs.

Main outcome measures: The proportion of general and methodological items reported, stratified by year and study design. Risk ratios with 95% confidence intervals were calculated to represent changes in reporting between 2000 and 2006.

Results: The majority of trials were two arm (379/519 (73%) in 2000 v 468/616 (76%) in 2006) parallel group studies (383/519 (74%) v 477/616 (78%)) published in specialty journals (482/519 (93%) v 555/616 (90%)). In both 2000 and 2006, a median of 80 participants were recruited per trial for parallel group trials. The proportion of articles that reported drug trials decreased between 2000 and 2006 (from 393/519 (76%) to 356/616 (58%)), whereas the proportion of surgery trials increased (51/519 (10%) v 128/616 (21%)). There was an increase between 2000 and 2006 in the proportion of trial reports that included details of the primary outcome (risk ratio (RR) 1.18, 95% CI 1.04 to 1.33), sample size calculation (RR 1.66, 95% CI 1.40 to 1.95), and the methods of random sequence generation (RR 1.62, 95% CI 1.32 to 1.97) and allocation concealment (RR 1.40, 95% CI 1.11 to 1.76). There was no difference in the proportion of trials that provided specific details on who was blinded (RR 0.91, 95% CI 0.75 to 1.10).

Conclusions: Reporting of several important aspects of trial methods improved between 2000 and 2006; however, the quality of reporting remains well below an acceptable level. Without complete and transparent reporting of how a trial was designed and conducted, it is difficult for readers to assess its conduct and validity.

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Conflict of interest statement

Competing interests: All authors have completed the Unified Competing Interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare (1) No financial support for the submitted work from anyone other than their employer; (2) No financial relationships with commercial entities that might have an interest in the submitted work; (3) No spouses, partners, or children with relationships with commercial entities that might have an interest in the submitted work; (4) No non-financial interests that may be relevant to the submitted work. DGA is a member of the CONSORT executive group and SH works as a CONSORT senior research fellow.

Figures

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Fig 1 Identification of randomised trials from PubMed citations indexed in December 2006
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Fig 2 Differences in reporting of methodological items between 2000 and 2006
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Fig 3 Differences in reporting of methodological items between CONSORT endorsing and non-endorsing journals in 2006
See this image and copyright information in PMC

Comment in

  • The new CONSORT statement.
    Antes G. Antes G. BMJ. 2010 Mar 23;340:c1432. doi: 10.1136/bmj.c1432. BMJ. 2010. PMID: 20332507 No abstract available.

References

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