1. Department of Surgery, Division of Thoracic Surgery, McMaster University, Hamilton, ON, Canada
2. Department of Surgery, Division of Thoracic Surgery, Rouen Normandy University, Rouen Cedex, France
3. Department of Surgery, Division of Thoracic Surgery, University of Toronto, Toronto, ON, Canada
4. Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, FL
5. Department of Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada