A Scoping Review Focused on Cooperative Group Involvement in Surgical Randomized Controlled Trials

Surgical randomized controlled trials (RCTs) are increasingly conducted in complex, multicenter contexts. Despite growing emphasis on research transparency and rigor, concerns remain regarding the methodological and ethical standards of such trials. Cooperative groups (CGs), well-established in oncology research, may play a role in improving trial quality in surgery-a domain where their influence remains underexplored. This scoping review aims to map the methodological and ethical quality of phase III surgical RCTs published between 2016 and 2020 in international surgical journals, with a focus on the potential impact of CG involvement.

We systematically searched ten major surgical journals for RCTs published between January 2016 and December 2020. Eligible trials were assessed using the Jadad scale (methodological quality) and the Berdeu score (ethical quality). We recorded study characteristics including sample size, funding source, multicenter design, and presence of a CG.

A total of 520 surgical RCTs were included. The mean Jadad score was 10.0 (±1.54) and the mean Berdeu score was 0.8 (±0.11). Only 50 trials (10%) involved a CG. These trials showed a trend toward higher methodological quality (mean Jadad 10.4 versus 9.97; P = 0.0593) and more frequent inclusion of quality-of-life assessments (28% versus 13%; P = 0.0056). Public funding was significantly more common in CG-led trials (56% versus 33%; P < 0.001).

This scoping review highlights that CG involvement in surgical RCTs is still limited but may be associated with improved methodological practices and broader outcome measures, such as quality of life. These findings suggest that greater involvement of CGs could strengthen research infrastructure and make surgical trials more patient-centered.