Masoud Behzadifar1, Meysam Behzadifar2, Nicola Luigi Bragazzi3. 1. Health Management and Economics Research Center, Iran University of Medical Sciences, Tehran, Iran. 2. Department of Epidemiology, Faculty of Health and Nutrition, Lorestan University of Medical Sciences, Khorramabad, Iran. 3. School of Public Health, Department of Health Sciences (DISSAL), University of Genoa, Genoa, Italy.