1. Korea University College of Medicine, Seongbuk-gu, Seoul, Korea
2. Division of Rheumatology, Department of Internal Medicine, Korea University Ansan Hospital, Danwon-gu, Ansan-si, Gyeonggi-do, Korea
3. Soksiwon Clinic, Michuhol-gu, Incheon, Korea
4. Division of Rheumatology, Department of Internal Medicine, Korea University Guro Hospital, Guro-gu, Seoul, Korea
5. Division of Rheumatology, Department of Internal Medicine, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung-si, Gangwon-do, Korea