1. Department of Internal Medicine, Seoul National University College of Medicine, Bundang Hospital, Seongnam, Korea.
2. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
3. Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
4. Department of Internal Medicine, Sungkyunkwan University College of Medicine, Samsung Medical Center, Seoul, Korea.
5. Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
6. Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
7. Department of Internal Medicine, Yonsei University Wonju Christian Hospital, Wonju, Korea.
8. Department of Internal Medicine, Gachon University Gil Hospital, Incheon, Korea.
9. Department of Internal Medicine, Chungnam National University College of Medicine, Daejoen, Korea.
10. Department of Internal Medicine, Chonnam National University College of Medicine, Gwangju, Korea.
11. Department of Internal Medicine, Yonsei University Severance Hospital, Seoul, Korea.
12. Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, Korea.
13. Department of Internal Medicine, Keimyung University College of Medicine, Daegu, Korea.
14. Department of Internal Medicine, Kyungpook National University College of Medicine, Daegu, Korea.
15. Department of Internal Medicine, Dongguk University College of Medicine, Ilsan Hosptial, Goyang, Korea.
16. Department of Internal Medicine, Konkuk University Medical Center, Seoul, Korea.