1. Center for Cohort Studies; Total Healthcare Center, Kangbuk Samsung Hospital; Sungkyunkwan University School of Medicine; Seoul South Korea
2. Department of Occupational and Environmental Medicine; Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine; Seoul South Korea
3. Department of Clinical Research Design & Evaluation; SAIHST, Sungkyunkwan University; Seoul South Korea
4. Division of Gastroenterology and Hepatology, Department of Internal Medicine; Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine; Seoul South Korea
5. Department of Family Medicine; Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine; Seoul South Korea