[1] Uk Ctr Tobacco & Alcohol Studies, Stirling, Scotland
[2] Univ Cambridge, Behav & Hlth Res Unit, Cambridge, England
[3] Univ Stirling, Sch Nursing & Midwifery, Stirling, Scotland
[4] Univ Glasgow, Paediat Epidemiol & Child Hlth Unit, Glasgow, Lanark, Scotland
[5] Univ Paris, Fac Med, Hop Pitie Salpetriere, Paris, France