1. Division of Rheumatology, Department of Internal Medicine, Gil Medical Center, Gachon University College of Medicine, Incheon, Korea.
2. Division of Rheumatology, Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, Korea.
3. Division of Rheumatology, Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.
4. Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital, Seoul, Korea.
5. Department of Rheumatology, Ajou University School of Medicine, Suwon, Korea.
6. Division of Rheumatology, Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
7. Division of Rheumatology, Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea.
8. Division of Rheumatology, Department of Internal Medicine, Pusan National University School of Medicine, Busan, Korea.
9. Division of Rheumatology, Department of Internal Medicine, Chung-Ang University School of Medicine, Seoul, Korea.