1. Tabriz Rheumatology Research Team; Tabriz University of Medical Sciences; Tabriz; Iran
2. Department of Internal Medicine; Division of Rheumatology; Army University of Medical Sciences; Tehran; Iran
3. Department of Internal Medicine, Division of Rheumatology; Kashan University of Medical Sciences; Kashan; Iran
4. Department of Internal Medicine, Division of Rheumatology; Tabriz University of Medical Sciences; Tabriz; Iran