1. Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
2. National Addictions Centre, Addictions Department, Institute of Psychiatry, Psychology and Neuroscience King’s College London, London, UK
3. Institute of Psychiatry, Psychology and Neuroscience, King’s Health Economics, King’s College London, London UK
4. Faculty of Health Sciences, Institute for Clinical and Applied Health Research (ICAHR), University of Hull, Hull, UK
5. Centre for Health Services Studies, University of Kent, Canterbury, Kent, UK
6. Institute for Mental Health, University of Birmingham, Birmingham, UK
7. Tavistock and Portman NHS Foundation Trust, London, UK
8. Division of Psychiatry, Department of Brain Sciences, Imperial College London, London, UK
9. Faculty of Medicine, University of Southampton, Southampton, UK
10. School of Cancer & Pharmaceutical Sciences, King’s College London, London, UK
11. Research Department of Practice and Policy, UCL School of Pharmacy, University College London, London, UK
12. Institute of Psychiatry Psychology and Neuroscience, Department of Psychology, King’s College London, London, UK