1. Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
2. Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
3. Department of Otolaryngology –Head and Neck Surgery, University of Ottawa, Ontario, Canada
4. Clinical Epidemiology Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, Ontario, Canada
5. Division of Neurology, Department of Internal Medicine, University of Ottawa, Ontario, Canada