1. Collaboration for Epidemiology of Ocular Diseases (CEPOD), Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
2. Department of Anesthesiology, Pharmacology, and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
3. Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
4. Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
5. Department of Ophthalmology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada