1 Division of Hematology, Department of Medicine, Memorial University of Newfoundland, Eastern Health, St John's.
2 Centre for Clinical Epidemiology and Community Studies, Jewish General Hospital, Montreal; Department of Medicine, McGill University, Montreal.
3 Thrombosis Program, Division of Hematology, Department of Medicine, University of Ottawa; Clinical Epidemiology Unit, Ottawa Health Research Institute, The Ottawa Hospital, Ottawa.