1. Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea.
2. Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
3. Department of Internal Medicine, Jeju National University School of Medicine, Jeju, Korea.
4. Department of Internal Medicine, Cheonan Hospital, Soon Chun Hyang University College of Medicine, Cheonan, Korea.
5. Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.
6. Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Incheon, Korea.
7. Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
8. Department of Internal Medicine, Kyungpook National University Medical Center, Daegu, Korea.
9. Department of Internal Medicine, Daegu Fatima Hospital, Daegu, Korea.
10. Department of Internal Medicine, Dongguk University College of Medicine Gyeongju Hospital, Gyeongju, Korea.
11. Department of Internal Medicine, Pusan Paik Hospital, Inje University College of Medicine, Busan, Korea.
12. Department of Gastroenterolgy, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Bucheon, Korea.
13. Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea.
14. Department of Internal Medicine, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
15. Department of Internal Medicine, Konyang University College of Medicine, Daejeon, Korea.
16. Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
17. Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.
18. Department of Biomedical Science, Seoul National University Graduate School, Seoul, Korea.
19. Cancer Research Institute, Seoul National University, Seoul, Korea.