1. Department of Population Health Sciences, King’s College, London
2. College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
3. Department of General Surgery, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
4. Department of Medicine, Houston Methodist Hospital, Houston, TX, USA
5. Department of Orthopedic Surgery, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
6. Department of Medicine, Division of Gastroenterology, King Abdullah Bin Abdulaziz University Hospital,Riyadh, Saudi Arabia
7. Department of Medicine, Division of Gastroenterology, King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia
8. Department of Medicine, Section of Gastroenterology, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia