1. Division of Colorectal Surgery, Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
2. Division of Colorectal Surgery, Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Korea.
3. Division of Colorectal Surgery, Department of Surgery, Myongji Hospital, Goyang, Korea.
4. Division of Colorectal Surgery, Department of Surgery, Dongnam Institute of Radiological and Medical Sciences, Busan, Korea.
5. Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea.