[1] OCTRF HAMILTON REG CANC CTR,HAMILTON,ON,CANADA
[2] MCMASTER UNIV,DEPT CLIN EPIDEMIOL & BIOSTAT,HAMILTON,ON,CANADA
[3] PRINCESS MARGARET HOSP,TORONTO,ON L8V 5C2,CANADA
[4] TORONTO HOSP,TORONTO,ON L8V 5C2,CANADA
[5] N YORK GEN HOSP,TORONTO,ON L8V 5C2,CANADA