1. Department of Clinical Sciences, College of Medicine, Dar Al Uloom University, Riyadh, Saudi Arabia
2. Departments of Emergency Medicine and Critical Care, College of Medicine, King Saud University, Riyadh, Saudi Arabia
3. Department of Family and Community Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia
4. Department of Medicine, Hematology/Oncology Division (Oncology Center), College of Medicine, King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia