[1] Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[2] Univ Hlth Network, Toronto Gen Hosp Res Inst, Toronto, ON, Canada
[3] St Michaels Hosp, Li Ka Shing Knowledge Inst, MAP Ctr Urban Hlth Solut, 209 Victoria St, Toronto, ON M5B 1T8, Canada
[4] British Columbia Ctr Dis Control, Vancouver, BC, Canada
[5] Univ British Columbia, Fac Med, Vancouver, BC, Canada
[6] Womens Coll Hosp, Womens Coll Res Inst, Toronto, ON, Canada
[7] Ottawa Hosp, Ottawa Hosp Res Inst, Ottawa, ON, Canada
[8] Univ Ottawa, Fac Med, Dept Epidemiol & Publ Hlth, Ottawa, ON, Canada
[9] Univ Toronto, Fac Med, Dept Family & Community Med, Toronto, ON, Canada