aNational Addictions Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
bCentre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
cInstitute for Social Science Research, The University of Queensland, Brisbane, Australia
dSouth London and Maudsley NHS Trust, London, United Kingdom
eGlobal Drug Survey, London, United Kingdom
*Corresponding author. Address: National Addictions Centre, Institute of Psychiatry Psychology & Neuroscience, King's College London, 4 Windsor Walk, London SE5 8BB, United Kingdom. Tel.: +44 (0)20 7848 0664. E-mail address: [email protected] (K. I. Morley).
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