1. Department of Internal Medicine, Hanyang University College of Medicine, Seoul, Korea.
2. Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea.
3. Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea.
4. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
5. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
6. Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, Korea.
7. Department of Internal Medicine, College of Medicine, Wonkwang University, Iksan, Korea.
8. Department of Internal Medicine, Chonnam University College of Medicine, Gwangju, Korea.
9. Department of Internal Medicine, Inje University College of Medicine, Busan, Korea.