Esben Houborg1, Bagga Bjerge2, Kari Lancaster3, Lynda Berends4. 1. Center for Alcohol and Drug Research, Aarhus BSS, Aarhus University, Denmark. Electronic address: eh.crf@psy.au.dk. 2. Center for Alcohol and Drug Research, Aarhus BSS, Aarhus University, Denmark. 3. Centre for Social Research in Health, University of New South Wales, Sydney, Australia. 4. National Drug & Alcohol Research Centre, University of New South Wales, Sydney, Australia; TRACE Research.