1. National Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK;
2. Health Psychology Section, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK;
3. Faculdade De Medicina, Preventative Medicine, Universidade De Sao Paulo, Sao Paulo, Brazil;
4. South London and Maudsley NHS Foundation Trust, Addictions Clinical Academic Group, London, UK;
5. Subdirecció General de Drogodependències, Barcelona, Spain;
6. Institute of Neuropsychiatry and Addictions, IMIM-Institut Hospital Del Mar D’investigacions Mèdiques, Barcelona, Spain;
7. Department of General Practice, University of Melbourne, Melbourne, Australia