Sohrab Iranpour1,2, Siamak Sabour3,4. 1. Department of Community Medicine, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran. 2. Social Determinants of Health Research Center, Ardabil University of Medical Sciences, Ardabil, Iran. 3. Department of Clinical Epidemiology, School of Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, I, Iran. 4. Safety Promotions and Injury Prevention Research Centre, Shahid Beheshti University of Medical Sciences, Tehran, I, Iran.