1. Department of Public Health, An Najah National University , Nablus, West Bank 7, Palestine
2. Department of Epidemiology, High Institute of Public Health, Alexandria University , 165 El-Horreya Ave. El-Hadara, Alexandria, Egypt
3. Department of Nutrition, High Institute of Public Health, Alexandria University , 165 El-Horreya Ave. El-Hadara, Alexandria, Egypt