1. Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
2. Department of Rheumatology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
3. Rheumatic Diseases Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
4. Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran