1. Department of Internal Medicine, Jeju National University School of Medicine, Jeju, Korea
2. Department of Internal Medicine, Inje University College of Medicine, Seoul, Korea
3. Department of Internal Medicine, Soonchunhyang University College of Medicine, Seoul, Korea
4. Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea
5. Department of Internal Medicine, Dongguk University College of Medicine, Goyang, Korea
6. Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea
7. Department of Gastroenterology, University of Ulsan College of Medicine, Seoul, Korea
8. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
9. Department of Internal Medicine, Hallym University College of Medicine, Anyang, Korea
10. Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea
11. Department of Internal Medicine, Inje University College of Medicine, Busan, Korea
12. Department of Internal Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea
13. Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea
14. Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, Korea
15. Department of Internal Medicine, Ajou University School of Medicine, Suwon, Korea