It is not clear whether closure of mucosal defects with clips after colonic endoscopic mucosal resection (EMR) prevents delayed bleeding, although it seems to have no protective effects when risk is low. We performed a randomized trial to evaluate the efficacy of complete clip closure of large (≥2 cm) large nonpedunculated colorectal lesions (LNPCLs) after EMR in patients with an estimated average or high risk of delayed bleeding