[1] Univ Toronto, Dept Surg, Toronto, ON, Canada
[2] St Michaels Hosp, Dept Surg, Toronto, ON, Canada
[3] Womens Coll Hosp, Dept Surg, Toronto, ON, Canada
[4] Mt Sinai Hosp, Dept Surg, Toronto, ON, Canada
[5] Univ Toronto, Dept Anesthesia, Toronto, ON, Canada
[6] St Michaels Hosp, Dept Anesthesia, Toronto, ON, Canada
[7] Toronto Gen Hosp, Dept Anesthesia & Pain Management, Toronto, ON, Canada
[8] St Michaels Hosp, Li Ka Shing Knowledge Inst, Toronto, ON, Canada
[9] Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[10] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[11] Univ Toronto, Inst Med Sci, Toronto, ON, Canada