1. Department of Epidemiology, School of Public Health; Shahid Beheshti University of Medical Sciences; Tehran Iran
2. Department of Epidemiology & Biostatistics, School of Public Health; Tehran University of Medical Sciences; Tehran Iran
3. Managerial Epidemiology Research Center, Department of Public Health, School of Nursing and Midwifery; Maragheh University of Medical Sciences; Maragheh Iran
4. Department of Public Health, School of Public Health; Zabol University of Medical Sciences; Zabol Iran
5. Department of Epidemiology, School of Public Health; Hamadan University of Medical Sciences; Hamadan Iran
6. School of Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran