[1] Univ Toronto, Interdept Div Crit Care, Toronto, ON, Canada
[2] Sunnybrook Hlth Sci Ctr, Dept Crit Care Med, Toronto, ON M4N 3M5, Canada
[3] Univ Hlth Network, Dept Med, Toronto, ON, Canada
[4] Univ Hlth Network, Krembil Neurosci Ctr, Toronto, ON, Canada
[5] Univ Hlth Network, Womens Hlth Program, Toronto, ON, Canada
[6] Univ Toronto, Dept Med, Toronto, ON, Canada
[7] Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[8] McMaster Univ, Dept Clin Epidemiol & Biostat, Hamilton, ON, Canada