[1] Univ Calgary, Calgary, AB, Canada
[2] Western Univ, Dept Med, Div Hematol, London, ON, Canada
[3] Western Univ, Dept Epidemiol & Biostat, London, ON, Canada
[4] Univ Ottawa, Ottawa Hosp, Dept Med, Div Hematol, Ottawa, ON, Canada
[5] McGill Univ, Jewish Gen Hosp, Dept Med, Div Internal Med, Montreal, PQ, Canada