1. IFT Institut für Therapieforschung, München, Munich, Germany;
2. Centre for Social Research on Alcohol and Drugs (SoRAD), Stockholm University, Stockholm, Sweden;
3. Centre for Interdisciplinary Addiction Research, Hamburg University, Universitätsklinik Hamburg-Eppendorf, Klinik für Psychiatrie und Psychotherapie (W37), Hamburg, Germany;
4. Institute for Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany;
5. Centre for Addiction and Mental Health (CAMH), Toronto, ON, Canada;
6. Campbell Family Mental Health Research Institute, Toronto, ON, Canada;
7. Faculty of Medicine, Institute of Medical Science (IMS), University of Toronto, Medical Sciences Building, Toronto, ON, Canada;
8. Department of Psychiatry, University of Toronto, Toronto, ON, Canada;
9. Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada