[1] Univ Alberta, Fac Nursing, Edmonton, AB, Canada
[2] Univ Ottawa, Dept Pediat, Ottawa, ON K1N 6N5, Canada
[3] Univ Alberta, Dept Pediat, Edmonton, AB, Canada
[4] Univ Ottawa, Sch Nursing, Ottawa, ON K1N 6N5, Canada
[5] Univ Ottawa, Dept Epidemiol & Community Med, Ottawa, ON K1N 6N5, Canada
[6] Canadian Inst Hlth Res, Ottawa, ON, Canada
[7] Ottawa Hlth Res Inst, Clin Epidemiol Program, Ottawa, ON, Canada
[8] Univ Ottawa, Dept Med, Ottawa, ON K1N 6N5, Canada