[1] Univ British Columbia, Dept Family Practice, Res Off, Vancouver, BC V5Z 1L8, Canada
[2] Univ Manitoba, Dept Community Hlth Sci, Winnipeg, MB R3T 2N2, Canada
[3] Vancouver Coastal Hlth Res Inst, Ctr Clin Epidemiol & Evaluat, Vancouver, BC, Canada
[4] UBC Ctr Hlth Serv & Policy Res, Vancouver, BC, Canada
[5] Univ Toronto, Dept Hlth Policy Management & Evaluat, Toronto, ON M5S 1A1, Canada