1 Community Medicine Department, Hamad Medical Corporation (HMC), Doha, Qatar. Electronic address: MAbedAlah@hamad.qa.
2 Community Medicine Department, Hamad Medical Corporation (HMC), Doha, Qatar.
3 Public health and preventive medicine department, Cairo University, Egypt; Community Medicine Department, Primary Health Care Corporation (PHCC), Doha, Qatar.
4 Community Medicine Department, Primary Health Care Corporation (PHCC), Doha, Qatar; Community Medicine Department, College of Medicine, Sousse University, Tunisia.