1. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
2. Department of Internal Medicine, Kosin University College of Medicine, Busan, Korea.
3. Department of Internal Medicine, College of Medicine, Hallym University, Chuncheon, Korea.
4. Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea.
5. Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
6. Department of Family Medicine, Jeju National University School of Medicine, Jeju, Korea.
7. Department of Internal Medicine, Jeju National University School of Medicine, Jeju, Korea.
8. Department of Internal Medicine, Dankook University College of Medicine, Cheonan, Korea.
9. Department of Internal Medicine and Institute of Health Science, Gyeongsang National University School of Medicine, Jinju, Korea.
10. Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.
11. Department of Internal Medicine, Seoul National University Healthcare System Gangnam Center and Healthcare Research Institute, Seoul, Korea.
12. Department of Internal Medicine, Wonkwang University School of Medicine, Iksan, Korea.