1. Department of Family and Community Medicine, College of Medicine, King Khalid University, P.O. Box 641, Abha 61421, Saudi Arabia
2. Department of Epidemiology, High Institute of Public Health, Alexandria University, Alexandria 21511, Egypt
3. Department of Community Medicine, College of Medicine Mansoura University, Mansoura 35516, Egypt
4. Department of Radiology, College of Applied Medical Sciences, King Khalid University, P.O. Box 641, Abha 61421, Saudi Arabia
5. Department of Internal Medicine, College of Medicine, King Khalid University, P.O. Box 641, Abha 61421, Saudi Arabia