1. Department of Population Health; New York University Langone Medical Center; New York City New York
2. Center for Drug Use and HIV Research; New York University College of Nursing; New York City New York
3. Drug Policy Modelling Program; National Drug and Alcohol Research Centre, UNSW; Sydney Australia
4. National Drug Research Institute; Faculty of Health Sciences; Curtin University; Perth Australia
5. Centre of Population Health; Burnet Institute; Melbourne Australia
6. Institute for Social Science Research; University of Queensland; Brisbane Australia
7. ARC Centre of Excellence for Children and Families over the Life Course; Institute for Social Science Research; The University of Queensland; Brisbane Australia
8. South London and Maudsley NHS Trust; London United Kingdom
9. Addictions Clinical Academic Group; King's College London, Maudsley Hospital; London United Kingdom
10. Global Drug Survey Ltd; London United Kingdom