1. From the Department of Medicine, King Faisal Specialist and Research Center, Riyadh, Saudi Arabia
2. From the National Research Centre, Cairo, Egypt
3. From the Johns Hopkins University Hospital, Aramco, Saudi Arabia
4. From the Ain Shams University Faculty of Medicine, Cairo, Egypt
5. From the Department of Biostatistics Epidemiology and Scientific Computing, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia