[1] McMaster Univ, Hamilton, ON, Canada
[2] Univ Toronto, Fac Med, Toronto, ON, Canada
[3] Womens Coll Hosp, Womens Coll Res Inst, 76 Grenville St, Toronto, ON, Canada
[4] Queens Univ, Dept Med, Kingston, ON, Canada
[5] Inst Clin Evaluat Sci, Toronto, ON, Canada
[6] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[7] Univ Massachusetts, Sch Med, Dept Med, Div Geriatr Med, Worcester, MA USA
[8] Univ Toronto, Dept Med, Toronto, ON, Canada