1. Division of Rheumatology, Seoul National University College of Medicine, Seoul, Korea.
2. Department of Rheumatology, Kyung Hee University Medical Center, Seoul, Korea.
3. Division of Rheumatology, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
4. Department of Rheumatology, The Catholic University of Korea, St. Vincent's Hospital, Suwon, Korea.
5. Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea.
6. Division of Rheumatology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
7. Department of Rheumatology, Kyung Hee University Hospital at Gangdong, Seoul, Korea.
8. Department of Rheumatology, Seoul National University Bundang Hospital, Seongnam, Korea.
9. Department of Rheumatology, Ajou University Hospital, Suwon, Korea.
10. Department of Rheumatology, Hallym University Sacred Heart Hospital, Anyang, Korea.
11. Department of Rheumatology, The Catholic University of Korea, Bucheon St. Mary's Hospital, Bucheon, Korea.
12. Department of Rheumatology, The Catholic University of Korea, Uijeongbu St. Mary's Hospital, Uijeongbu, Korea.
13. Division of Rheumatology, Inha University School of Medicine, Incheon, Korea.
14. Department of Rheumatology, Dong-A University Hospital, Busan, Korea.
15. Division of of Rheumatology, Kosin University Gospel Hospital, Busan, Korea.
16. Division of Rheumatology, Catholic University of Daegu School of Medicine, Daegu, Korea.
17. Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea.
18. Department of Rheumatology, Chonnam National University Medical School, Gwangju, Korea.
19. Division of Rheumatology, Chonbuk National University Medical School, Jeonju, Korea.
20. Department of Rheumatology, Konkuk University Medical Center, Seoul, Korea.