1. Division of Rheumatology; Department of Internal Medicine; NHIS Ilsan Hospital; Goyang-si South Korea
2. Division of Rheumatology; Department of Internal Medicine; Dankook University Hospital; Cheonan South Korea
3. Division of Rheumatology; Department of Internal Medicine; Seoul National University Bundang Hospital; Seongnam South Korea
4. Division of Rheumatology; Department of Internal Medicine; Yonsei University College of Medicine; Seoul South Korea