1. Health Economics Unit, School of Public Health and Family Medicine, Health Sciences Faculty , University of Cape Town, Anzio Road, Observatory, Cape Town 7925, South Africa
2. Curtin enAble Institute, Faculty of Health Sciences, Curtin University, Kent Street , Bentley, Perth, WA 6102, Australia
3. Alcohol, Tobacco and Other Drug Research Unit, South African Medical Research Council , Francie van Zyl Drive, Tygerberg, Cape Town 7505, South Africa
4. Division of Addiction Psychiatry, Department of Psychiatry and Mental Health, 1st Floor, Neuroscience Institute, Groote Schuur Hospital , University of Cape Town, Observatory, Cape Town 7925, South Africa
5. Alan J Flisher Centre for Public Mental Health, Department of Psychiatry and Mental Health, University of Cape Town , 46 Sawkins Road, Rondebosch, Cape Town 7700, South Africa
6. School of Health and Related Research, University of Sheffield, Regent Court, 30 Regent Street , Sheffield, S1 4DA, UK
7. Centre for Global Mental Health, Health Service and Population Research Department, Institute of Psychiatry, Psychology and Neuroscience, King’s Global Health Institute , King’s College London, De Crespigny Park, London, SE5 8AF, UK