1. Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea.
2. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
3. Department of Internal Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea.
4. Digestive Disease Center, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
5. Department of Internal Medicine, Hallym University College of Medicine, Chuncheon, Korea.
6. Department of Internal Medicine, Eulji University School of Medicine, Seoul, Korea.
7. Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea.
8. Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea.
9. Department of Internal Medicine, Pusan National University School of Medicine and Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
10. Department of Internal Medicine and Research Institute, Soonchunhyang University College of Medicine, Bucheon, Korea.
11. Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
12. Department of Internal Medicine, Wonkwang University School of Medicine, Iksan, Korea.
13. Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
14. Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.