1. University of Bath; Addiction and Mental Health Group (AIM), Department of Psychology; Bath UK
2. Institute of Psychiatry, Psychology & Neuroscience, King's College London; UK Centre for Tobacco and Alcohol Studies, National Addiction Centre; London UK
3. University of Birmingham; Public Health, Epidemiology and Biostatistics; Edgbaston Birmingham West Midlands UK B15 2TT
4. University of Oxford; Nuffield Department of Primary Care Health Sciences; Radcliffe Observatory Quarter Woodstock Road Oxford Oxfordshire UK OX2 6GG