1. Queen's University School of Medicine, Kingston, Canada
2. Department of Otolaryngology–Head and Neck Surgery, Children's Hospital at London Health Sciences Centre, and Schulich School of Medicine and Dentistry, University of Western Ontario, Box 5010, 800 Commissioners Road E, N6A 5W9, London, ON, Canada
3. Department of Otolaryngology–Head and Neck Surgery, St Michael's Hospital, University of Toronto, Toronto, ON, Canada