1. Department of Medicine, Cumming School of Medicine, University of Calgary , Calgary, AB T2T 5C7 , Canada
2. Division of Geriatrics, Department of Medicine, University of California (SanFrancisco) , San Francisco, CA 94121 , USA
3. Geriatrics, Palliative and Extended Care Service Line, SanFrancisco VA (Veterans Affairs) Health Care System , San Francisco, CA 94121 , USA
4. Department of Medicine (Division of Nephrology) and the Ottawa Hospital Research Institute, University of Ottawa , Ottawa, ON K1H 7W9 , Canada
5. Library and Cultural Resources, University of Calgary , Calgary, AB T2N 4N1 , Canada
6. Departments of Surgery and Oncology, University of Calgary , Calgary, AB T2N 2T9 , Canada
7. Department of Epidemiology and Biostatistics, University of California (SanFrancisco) , San Francisco, CA 94158 , USA
8. Department of Community Health Sciences, Cumming School of Medicine, University of Calgary , Calgary, AB T2N 4Z6 , Canada