[1] Ottawa Hosp Res Inst, Clin Epidemiol Program, Ottawa, ON K1Y 4E9, Canada
[2] Karolinska Inst, Dept Publ Hlth Sci, Stockholm, Sweden
[3] Publ Hlth Ontario, Toronto, ON, Canada
[4] Univ Toronto, Dalla Lana Sch Publ Hlth, Toronto, ON, Canada
[5] Univ Ottawa, Dept Med, Ottawa, ON, Canada
[6] Univ Ottawa, Dept Epidemiol & Community Med, Ottawa, ON, Canada