1. Respiratory Epidemiology and Clinical Research Unit, Research Institute of the McGill University Health Centre, Montreal, Québec, Canada;
2. Department of Medicine, McGill University, Montreal, Québec, Canada;
3. Department of Medicine, Columbia University Medical Center, New York, New York;
4. Southern Ontario Centre for Atmospheric Aerosol Research, Department of Chemical Engineering and Applied Chemistry,
5. Dalla Lana School of Public Health, and
6. Ottawa Hospital Research Institute, Ottawa University, Ottawa, Ontario, Canada;
7. Toronto General Hospital Research Institute, University of Toronto, Toronto, Ontario, Canada;
8. Division of Respirology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada;
9. Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada;
10. Respiratory Research Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada;
11. Division of Respiratory and Critical Care Medicine, Queen's University, Kingston, Ontario, Canada;
12. Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada;
13. Department of Medicine, University of Calgary, Calgary, Alberta, Canada;
14. GlaxoSmithKline, Mississauga, Ontario, Canada;
15. GlaxoSmithKline, Québec City, Québec, Canada;
16. GlaxoSmithKline, Brentford, United Kingdom; and
17. GlaxoSmithKline, Collegeville, Pennsylvania