[1] Univ Ottawa, Dept Med, Thrombosis Program, Div Hematol, Ottawa, ON, Canada
[2] Ottawa Gen Hosp, Clin Epidemiol Program, Res Inst, Ottawa, ON K1H 8L6, Canada
[3] Univ Ottawa, Dept Med, Bone Marrow Transplant Program, Div Hematol, Ottawa, ON, Canada