1. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
2. Department of Internal Medicine, Gachon University Gil Hospital, Incheon, Korea.
3. Department of Internal Medicine, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
4. Department of Internal Medicine, Catholic University of Daegu, Daegu, Korea.
5. Department of Internal Medicine, Daegu Fatima Hospital, Daegu, Korea.
6. Department of Internal Medicine, Seoul Veterans Hospital, Seoul, Korea.
7. Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.