[1] Univ Alberta, Sch Publ Hlth, Dept Publ Hlth Sci, Edmonton, AB T6G 2G3, Canada
[2] Univ Alberta, Alberta Ctr Injury Control & Res, Edmonton, AB T6G 2G3, Canada
[3] Karolinska Inst, Inst Environm Med, Dept Epidemiol, S-10401 Stockholm, Sweden
[4] Uppsala Univ, Dept Med Sci Occupat & Environm Med, Uppsala, Sweden
[5] Univ Alberta, Dept Med, Edmonton, AB, Canada
[6] Toronto Western Res Inst, Div Hlth Care Outcomes & Res, CREIDO, Toronto, ON, Canada
[7] Univ Toronto, Fac Med, Dalla Lana Sch Publ Hlth Sci, Toronto, ON, Canada
[8] Univ Toronto, Fac Med, Dept Hlth Policy Management & Evaluat, Toronto, ON, Canada