1. Division of Gastrointestinal Surgery, Department of Surgery, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Artificial Intelligence and Big-Data Convergence Center, Gil Medical Center, Gachon University College of Medicine and Science, Incheon, Korea.
3. Graduate School of Public Health, Seoul National University, Seoul, Korea.
4. Departement of Preventive Medicine, Gachon University College of Medicine, Incheon, Korea.