1. Epidemiology & Biostatistics Department, School of Public Health, Neyshabur University of Medical, Sciences, Neyshabur, Iran
2. Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran
3. Student Research Committee, Neyshabur University of Medical Sciences, Neyshabur, Iran
4. Department of Epidemiology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
5. Noncommunicable Diseases Research Center, Neyshabur University of Medical Sciences, Neyshabur, Iran