Conflicts of Interest and Industry Influence in Randomized Controlled Trials in Hand Surgery: A Systematic Review

To verify the association between the presence of conflict of interests and pro-funder results in randomized controlled trials (RCTs) in hand surgery. The secondary objective was to evaluate the influence of industry funding on the bibliometric characteristics of these RCTs.

We examined 178 RCTs published between 2013 and 2023 in 5 high-impact journals focusing on the hand, wrist, elbow, or peripheral nerves in the MEDLINE, Embase, and Scopus databases. From the studies included, we assessed the presence of a declared conflict of interests and analyzed its association with the primary outcome (favorable vs. unfavorable). We additionally evaluated the association with other variables, including compliance with the Consolidated Standards of Reporting Trials (CONSORT) guidelines, the number of authors, and journal impact factors. The risk of bias in the included studies was assessed using the Risk of Bias 2 (RoB 2) tool. All assessments were performed by two independent reviewers, following a previously defined protocol. This systematic review was not previously recorded on public platforms such as International Prospective Register of Systematic Reviews (PROSPERO).

We found no relationship between the presence of conflict of interests and pro-funder results (35.4% vs. 65.6%. p  = 0.503). Industry-funded studies have been published in journals with significantly higher impact factors than non-industry-funded studies (3.05 vs. 2.2) ( p  < 0.001), with a significant difference in the number of funded authors (1.84 vs. 0.07) ( p  < 0.001).

There was no significant association between the type of funding and the achievement of favorable results in randomized clinical trials in hand surgery. Funded studies were more frequently published in higher impact journals and showed greater adherence to the CONSORT checklist, but these characteristics did not translate into a greater risk of bias.