1. Division of Rheumatology, Department of Internal Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
2. Division of Rheumatology, Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
3. Division of Rheumatology, Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
4. Division of Rheumatology, Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
5. Division of Rheumatology, Department of Internal Medicine, Inha University School of Medicine, Incheon, Korea.
6. Hanyang University Hospital for Rheumatic Diseases, Seoul, Korea.
7. Division of Rheumatology, Department of Internal Medicine, Ajou University School of Medicine, Suwon, Korea.
8. Biomedical Research Group Brain Korea 21, Hanyang University, Seoul, Korea.