1. Department of Medicine, The University of British Columbia, Vancouver, Canada.
2. Department of Statistics, The University of British Columbia, Vancouver, Canada.
3. Centre for Emergency Preparedness and Response at the Department of Emergency Medicine, Zayed Military Hospital, Abu Dhabi, United Arab Emirates.
4. Department of Radiology, The University of Missouri-Kansas City School of Medicine, Kansas City, Missouri.
5. Department of Radiology, Vancouver General Hospital, The University of British Columbia, Vancouver, Canada.