Disclosure of funding sources and conflicts of interest in phase III surgical trials: Survey of ten general surgery journals

Abstract

Background: Discussions regarding disclosure of funding sources and conflicts of interest (COI) in published peer-reviewed journal articles are becoming increasingly more common and intense. The aim of the present study was to examine whether randomized controlled trials (RCTs) published in leading surgery journals report funding sources and COI. Methods: All articles reporting randomized controlled phase III trials published January 2005 through December 2010 were chosen for review from ten international journals. We evaluated the number of disclosed funding sources and COI, and the factors associated with such disclosures. Results: From a review of 657 RCT from the ten journals, we discovered that presence or absence of a funding source and COI was disclosed by 47 % (309) and 25.1 % (165), respectively. Most articles in "International Committee of Medical Journal Editors (ICMJE)-affiliated journals" did not disclose COI. Disclosure of funding was associated with a journal impact factor >3 (51.7 vs 41.6 %; p < 0.01), statistician/epidemiologist involvement (64.2 vs 43.7 %; p < 0.001), publication after 2008 (52.9 vs 41.1 %; p < 0.01), and the journal being ICMJE-affiliated (49.3 vs 40 %; p < 0.05). Conflict of interest disclosure was associated with publication after 2008 (38.7 vs 11.3 %; p < 0.001), and with the journal not being affiliated with ICMJE (36.9 vs 21.3 %; p < 0.001). Conclusions: Of the published studies we investigated, over half did not disclose funding sources (i.e., whether or not there was a funding source), and almost three quarters did not disclose whether COI existed. Our findings suggest the need to adopt best current practices regarding disclosure of competing interests to fulfill responsibilities to readers and, ultimately, to patients.