1. Department of Speech Therapy, School of Paramedical and Rehabilitation Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
2. Department of Speech Therapy, School of Rehabilitation Sciences, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
3. Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
4. School of Nursing, Illinois Wesleyan University, Bloomington, IL, USA
5. Department of Epidemiology, School of Health, Social Determinants of Health Research Center, Mashhad University of Medical Sciences, Mashhad, Iran, and
6. Student Research Committee, Department of Biostatistics, School of Health, Mashhad, Iran