1 Public Health and Social Policy, Faculty of Health, Canadian Institute for Substance Use Research, University of Victoria, Victoria, BC, Canada. urbanosk@uvic.ca.
2 Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
3 Department of Community Health and Epidemiology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.
4 School of Public Health, University of Alberta, Edmonton, AB, Canada.
5 Département de médecine sociale et préventive, École de santé publique de l'Université de Montréal, Montréal, QC, Canada.