1. Department of Epidemiology and Biological Statistics, Faculty of Health Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
2. Department of Health Education and Promotion, Faculty of Health Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
3. Department of Public Health, Khalkhal University of Medical Sciences, Khalkhal, Iran
4. Academic Unit of Medical Education, University of Southampton, Southampton, UK