1. Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, ON, Canada.
2. Department of Medicine, University of Ottawa, Ottawa, ON, Canada.
3. Department of Medicine, Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada.
4. Division of Thoracic Surgery, Department of Surgery, The Ottawa Hospital, Ottawa, ON, Canada.
5. Clinical Epidemiology Program, Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada.