Surgical trials and trial registries: a cross-sectional study of RCTs published in journals requiring trial registration in their author instructions

Tags: Poster
Hardt JLS1, Metzendorf M2, Meerpohl JJ3
1Department of Surgery, University Medical Centre Mannheim, University of Heidelberg, Mannheim, Germany, 2Library, University Medical Centre Mannheim, Mannheim, Germany, 3German Cochrane Centre, Institute of Medical Biometry and Medical Informatics, University Medical Center Freiburg, Freiburg, Germany

Background: Trial registries and results databases aim at preventing incomplete and delayed reporting, thus facilitating systematic reviews.

Objectives: To assess 1. Whether RCTs published in surgery journals requiring trial registration in their author instructions were indeed registered, 2. Whether study results of registered RCTs were submitted to the registry, thus publicly available.

Methods: Two authors analyzed author instructions of surgery-related journals with the highest impact factor (Journal Citation Reports 2011) regarding endorsement of trial registration in 01/2013. The 10 highest ranked journals requiring trial registration were chosen and a MEDLINE search for RCTs published in the included journals between June 1, 2012 and December 31, 2012 was conducted. Trials recruiting participants before 2004 were excluded because the International Committee of Medical Journal Editors first proposed comprehensive trial registration in September 2004. Then, the International Clinical Trials Registry Platform (ICTRP) was searched to assess whether RCTs identified were indeed registered and whether for registered RCTs results were available in the registry.

Results: Our search retrieved 588 citations. 460 clearly irrelevant references were excluded. Further 25 of the remaining 128 citations were excluded by full-text screening, e.g. because they had started patient recruitment prior to 2004. A total of 103 RCTs was finally included. 85 of these RCTs (83%) could be identified in the ICTRP (see Table 1). 49 RCTs registered on ClinicalTrials.gov were clearly obligated to submit results (> 12 months since completion date), but for only 7 (14%) of them results had been submitted to the Results Database (see Table 2).

Conclusions: Though still not fully implemented, trial registration in surgery has gained momentum. Nonetheless, further efforts should be made to achieve complete trial registration. Submitting study results to ClinicalTrials.gov remains poor. However, searching trial registers for results as part of a systematic review might complement information provided by journal publications.