1. Division of Gastroenterology, Department of Internal Medicine Yeouido St Mary's Hospital, College of Medicine, The Catholic University of Korea Seoul South Korea
2. Department of Biomedicine & Health Science College of Medicine, The Catholic University of Korea Seoul South Korea
3. Division of Gastroenterology, Department of Internal Medicine Eunpyung St Mary's Hospital, College of Medicine, The Catholic University of Korea Seoul South Korea
4. Division of Endocrinology and Metabolism, Department of Internal Medicine Yeouido St Mary's Hospital, College of Medicine, The Catholic University of Korea Seoul South Korea
5. Division of Gastroenterology, Department of Internal Medicine Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea Seoul South Korea
6. Department of Statistics and Actuarial Science Soongsil University Seoul South Korea