1. Trauma Surgery Section, Hamad General Hospital, P.O. Box 3050, Doha, Qatar
2. Clinical Research, Trauma Surgery Section, Hamad General Hospital, P.O. Box 3050, Doha, Qatar
3. Clinical Medicine, Weill Cornell Medical College, P.O. Box 24144, Doha, Qatar
4. Department of Surgery, Weill Cornell Medical College, P.O. Box 24144, Doha, Qatar
5. Department of Surgery, University of Arizona, P.O. Box 245005, Tucson, AZ, USA