1Ottawa Combined Adult Spinal Surgery Program, The Ottawa Hospital, Ottawa, ON, Canada
2Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
3Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
4Division of Orthopaedic Surgery, University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
5Division of Neurosurgery, University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
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