[1] Univ Toronto, Toronto, ON, Canada
[2] Cross Canc Inst, Edmonton, AB T6G 1Z2, Canada
[3] Tom Baker Canc Clin, Calgary, AB, Canada
[4] British Columbia Canc Agcy, Vancouver, BC V5Z 4E6, Canada
[5] Ottawa Reg Canc Ctr, Ottawa, ON K1Y 4K7, Canada
[6] Queen Elizabeth 2 Hlth Sci Ctr, Halifax, NS, Canada
[7] Princess Margaret Hosp, Toronto, ON M4X 1K9, Canada
[8] Princess Margaret Hosp, Dept Biostat, Toronto, ON M4X 1K9, Canada