1. Department of Internal Medicine, Soonchunhyang University College of Medicine, Seoul, Korea.
2. Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, Korea.
3. Department of Internal Medicine, Yonsei University, Wonju College of Medicine, Wonju, Korea.
4. Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea.
5. Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea.
6. Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
7. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
8. Department of Internal Medicine, Ewha Woman's University School of Medicine, Seoul, Korea.
9. Department of Internal Medicine, National Cancer Center, Goyang, Korea.
10. Department of Internal Medicine, Dankook University College of Medicine, Seoul, Korea.
11. Department of Internal Medicine, Hallym University College of Medicine, Seoul, Korea.
12. Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea.
13. Department of Internal Medicine, Sungkyunkwan University School of Medicine, Seoul, Korea.
14. Department of Internal Medicine, Konyang University College of Medicine, Daejeon, Korea.
15. Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea.