1. Isfahan Neurosciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
2. Department of Neurology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
3. Department of Biostatistics and Epidemiology, Faculty of Health, Isfahan University of Medical Sciences, Isfahan, Iran
4. Students’ Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran
5. Department of Biostatistics and Epidemiology, Faculty of Health, North Khorasan University of Medical Sciences, Bojnurd, Iran
6. Department of Neurology and Rehabilitation Medicine, Waddell center in Multiple Sclerosis, University of Cincinnati, Cincinnati, OH, USA