1. Division of Rheumatology, Korea University Anam Hospital, Seoul, Korea.
2. Division of Rheumatology, Korea University Guro Hospital, Seoul, Korea.
3. Division of Endocrinology, Korea University Guro Hospital, Seoul, Korea.
4. Division of Rheumatology, Catholic University of Daegu, Daegu, Korea.
5. Division of Rheumatology, Dong-A University, Busan, Korea.