1. Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea
2. Department of Gastroenterology, Ajou University School of Medicine, Suwon, Gyeonggi-do, Korea
3. Department of Internal Medicine, Catholic University College of Medicine, Seoul, Korea
4. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
5. Department of Internal Medicine, Soonchunhyang University College, Seoul, Korea
6. Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
7. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea
8. Department of Internal Medicine, Keimyung University College of Medicine, Daegu, Korea
9. Department of Internal Medicine, Wonkwang University College of Medicine, Iksan, Jeollabuk-do, Korea
10. Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea
11. Department of Internal Medicine, Konyang University College of Medicine, Daejeon, Korea
12. Department of Internal Medicine, Pusan National University College of Medicine, Busan, Korea
13. Department of Internal Medicine, Kangbuk Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
14. Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
15. Chonnam National University Medical School, Gwangju, Korea
16. Department of Internal Medicine, Inje University College of Medicine, Busan, Korea
17. Department of Internal Medicine, Catholic University of Daegu, School of Medicine, Daegu, Korea