1. Department of Community Health and Epidemiology, Dalhousie University, Halifax, NS B3H 4R2, Canada
2. Cancer Outcomes Research Program, Nova Scotia Health Authority, Halifax, NS B3H 2Y9, Canada
3. Department of Surgery, Nova Scotia Health Authority, Halifax, NS B3H 2Y9, Canada
4. Department of Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada