Improving evidence, but at what ethical price?

We read with interest the article by Miyakawa et al reporting that prophylactic clip closure after colorectal endoscopic submucosal dissection (ESD) reduces severe delayed bleeding.1 While recent correspondence highlights methodological concerns regarding the unusually high bleeding rate in the non-closure group,2 3 we would like to further raise concerns about the ethical aspects of the study design. Prior randomised controlled trials (RCTs), meta-analyses and US guidelines already support prophylactic closure after endoscopic mucosal resection (EMR) for proximal colon lesions≥20 mm.4–6 Despite this evidence, the present study randomised patients undergoing colorectal ESD—including those with 20–50 mm lesions in the right colon—into closure and …