1. Department of Rheumatology, Chonnam National University Medical School and Hospital, Gwangju, Korea.
2. Division of Rheumatology, Department of Internal Medicine, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea.
3. Division of Rheumatology, Department of Internal Medicine, Kyung Hee University Hospital at Gangdong, Kyung Hee University College of Medicine, Seoul, Korea.
4. Department of Rheumatology, Inje University Ilsan Paik Hospital, Goyang, Korea.
5. Division of Rheumatology, Department of Internal Medicine, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
6. Division of Rheumatology, Department of Internal Medicine, Inje University Haeundae Paik Hospital, Busan, Korea.
7. Department of Internal Medicine, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Korea.
8. Division of Rheumatology, Department of Internal Medicine, National Medical Center, Seoul, Korea.
9. Department of Internal Medicine, The Catholic University of Korea, Seoul St. Mary's Hospital, Seoul, Korea.
10. Division of Rheumatology, Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, Korea.
11. Division of Rheumatology, Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
12. Division of Rheumatology, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
13. Division of Rheumatology, Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Korea.