Randomized sham-controlled trials in endoscopy: a systematic review and meta-analysis of adverse events.

Sham procedures in endoscopy are used with the intention of controlling for placebo response, potentially allowing more precise evaluation of treatment effect. Nevertheless, this type of study may impose significant risk without potential benefit for those in the sham group. The aim of the current study was to systematically review and analyze the endoscopic literature to assess the safety of sham controls.