Publication of sports medicine-related randomized controlled trials registered in ClinicalTrials.gov.

BACKGROUND

There is increasing evidence that a significant proportion of randomized trials in medicine, and recently in orthopaedics, do not go on to publication.

PURPOSE

The objectives of this study were (1) to determine publication rates of randomized controlled trials in sports medicine that have been registered with ClinicalTrials.gov (CTG) and (2) to compare the registration summaries of randomized trials on CTG with final published manuscripts on pertinent methodological variables.

STUDY DESIGN

Systematic review.

METHODS

Two independent investigators searched ClinicalTrials.gov for all closed and completed trials related to sports medicine until June 2009 using a text search strategy. The authors then searched for publications resulting from these registered trials in peer-reviewed journals that are indexed with MEDLINE and/or EMBASE as of February 2012 based on study authors and key words provided in the study protocol. Details of primary outcomes and secondary outcomes, study sponsors, and sample size were extracted and compared between registrations and publications.

RESULTS

Of 34 closed and completed trials registered on CTG, there were 20 resultant publications in peer-reviewed journals (58.8%). There was no significant relationship between source of funding and rate of publication (P > .05). The authors found a discrepancy between the CTG registration summary and the manuscript in at least one methodological variable (primary/secondary outcomes, inclusion/exclusion criteria, sample size) in 16 of 20 (80.0%) articles and a discrepancy in the primary outcome in 8 of 20 (40.0%) published trials.

CONCLUSION

Although registration of sports medicine trials in CTG does not consistently result in publication or disclosure of results at 32 months from the time of study completion, observed publication rates are higher than in other orthopaedic subspecialties. Changes are also frequently made to the final presentation of eligibility criteria and primary and secondary outcomes that are not reflected in the registered trial data.