[1] Univ Calgary, Rm C231 Foothills Med Ctr, Cumming Sch Med, Dept Emergency Med, Calgary, AB, Canada
[2] Univ Calgary, Rm C231 Foothills Med Ctr, Cumming Sch Med, Dept Community Hlth Sci, Calgary, AB, Canada
[3] Univ Hlth Network, Dept Emergency Med, Toronto, ON, Canada
[4] Univ Toronto, Dept Med, Div Emergency Med, Toronto, ON, Canada
[5] Sunnybrook Hlth Sci Ctr, Sunnybrook Res Inst, Toronto, ON, Canada