1 Division of Rheumatology, Department of Internal Medicine, Soonchunhyang University School of Medicine, Seoul, South Korea.
2 Division of Rheumatology, Department of Internal Medicine, Wonkwang University Hospital, Iksan, South Korea.
3 International Healthcare Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
4 Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, South Korea.
5 Division of Rheumatology, Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, South Korea.
6 Division of Rheumatology, Department of Internal Medicine, School of Medicine, Chungnam National University, Chungnam National University Hospital, Daejeon, South Korea.
7 Division of Rheumatology, Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
8 Division of Rheumatology, Department of Internal Medicine, Gachon University College of Medicine, Gil Medical Center 21, Namdong-daero 774 beon-gil, Namdong-gu, Incheon, 21565, South Korea. baekhj@gilhospital.com.