1. Schwartz/Reisman Emergency Medicine Institute, University of Toronto, Toronto, Ontario, Canada
2. Department of Emergency Medicine, Mt Sinai Hospital, Toronto, Ontario, Canada
3. Department of Family & Community Medicine, University of Toronto, Toronto, Ontario, Canada
4. ICES, Toronto, Ontario, Canada
5. Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael’s Hospital, Toronto, Ontario, Canada
6. Departments of Medicine and Obstetrics and Gynecology, St Michael’s Hospital, Toronto, Ontario, Canada