1. Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
2. Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
3. Refractive Errors Research Center, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
4. College of Optometry, Pacific University, Forest Grove, Oregon, USA
5. Eye Research Center, Mashhad University of Medical Sciences, Mashhad, Iran