1. Department of Internal Medicine; Pusan National University School of Medicine and Biomedical Research Institute; Pusan National University Hospital; Busan Korea
2. Department of Internal Medicine; Busan Paik Hospital; Inje University College of Medicine; Busan Korea
3. Department of Internal Medicine; The Catholic University of Korea College of Medicine; Seoul Korea
4. Department of Internal Medicine; Inje University College of Medicine; Seoul Korea
5. Division of Gastroenterology; Department of Internal Medicine; Yonsei University College of Medicine; Seoul Korea
6. Department of Internal Medicine; Kyungpook National University Hospital; Daegu Korea
7. Department of Internal Medicine; Soonchunhyang University School of Medicine; Cheonan Korea
8. Department of Internal Medicine; Jeju National University School of Medicine; Jeju Korea
9. Department of Internal Medicine; Digestive Disease Research Institute; Wonkwang University College of Medicine; Iksan Korea
10. Department of Internal Medicine; Hallym University College of Medicine; Chuncheon Korea