1. From the Department of Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada; the Department of Psychiatry, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada; the Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; the Centre for Addiction and Mental Health, Toronto, Ontario, Canada; and the Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.