1. The Medical School, Newcastle University; Institute of Health and Society; Newcastle upon Tyne UK NE2 4HH
2. Newcastle University; Institute of Health and Society; 21 Claremont Place Newcastle upon Tyne Tyne & Wear UK NE2 4AA
3. Newcastle University; Institute of Health & Society; 21 Claremont Place Newcastle upon Tyne Tyne and Wear UK NE2 4AA
4. University of Sheffield; School of Health and Related Research; Regent Street Sheffield UK S1 4DA
5. Prince Charles Hospital; Centre for Drug & Alcohol Studies; Brisbane Queensland Australia QLD 4000
6. University of Northumbria; Division of Psychology; ELLISON BUILDING ELLISON PLACE NEWCASTLE UPON TYNE UK NE1 8ST
7. Royal Brisbane and Women's Hospital; Department of Psychiatry; Centre for Drug & Alcohol Studies School of Medicine University of Queensland/Royal Brisbane Hospital Australia QLD 4029
8. Centre Hospitalier Vaudois and University of Lausanne; Health Care Evaluation Unit & Clinical Epidemiology Centre, Institute of Social and Preventive Medicine; Bugnon 17 CH-1005 Lausanne Switzerland
9. Medical Research Council; South African Cochrane Centre; PO Box 19070 Tygerberg South Africa 7505