1. Department of Public Health, Faculty of Health, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
2. Department of Biostatistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
3. Psychosomatic Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
4. Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
5. Department of Internal Medicine, School of Medicine and Integrative Functional, Gastroenterology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran