Author Contributions: Dr Straus had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: Straus.
Acquisition of data: Straus, Holroyd-Leduc.
Analysis and interpretation of data: Straus, Thorpe, Holroyd-Leduc.
Drafting of the manuscript: Straus.
Critical revision of the manuscript for important intellectual content: Straus, Thorpe, Holroyd-Leduc.
Statistical analysis: Straus, Thorpe.
Administrative, technical, or material support: Straus.
Financial Disclosures: None reported.
Funding/Support: Dr Straus is supported by a Tier 2 Canada Research Chair; Mr Thorpe and Dr Holroyd-Leduc are supported by the Knowledge Translation Program at the University of Toronto.
Role of the Sponsor: There was no external funding obtained for the design and conduct of the study, the collection, management, analysis, or for the interpretation of the data; or for the preparation, review, or approval of the manuscript.
Acknowledgment: We thank Darlyne Rath, Laure Perrier, and Desiree Chanderbhan for their assistance in the search and retrieval of relevant articles and the preparation of the manuscript as part of their normal duties. Richard Bedlack, MD, PhD, Division of Neurology, and Sheri Keitz, MD, PhD, Division of General Internal Medicine, Duke University, Durham, NC, and Kaveh Shojania, MD, Department of Medicine, University of Ottawa, Ottawa, Ontario, who provided useful feedback and suggestions on earlier drafts of the manuscript. We also thank Janis Miyasaki, MD, FRCPC, Department of Neurology, for comments on the figure. They received no compensation for their reviews of the manuscript.