1. The Ottawa Hospital Research Institute, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
2. Institute for Clinical Evaluative Sciences, Ontario, Canada
3. Department of Medicine, University of Toronto, Toronto, Ontario, Canada
4. Department of Medicine, St. Michael’s Hospital, Toronto, Ontario, Canada
5. Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; and
6. Sunnybrook Research Institute, Toronto, Ontario, Canada