n order to evaluate the effectiveness of a school-based substance abuse prevention programme developed in the EU-Dap study (European Drug Addiction Prevention trial, a cluster Randomised Controlled Trial was carried out in Seven European countries. The study included 170 schools (7079 pupils 12–14 years of age) who were randomly assigned to one of three experimental conditions or to a control condition during the school year 2004/2005. The programme consisted of a 12hr curriculum based on a comprehensive social influence approach. A pre-test survey assessing past and current substance use was conducted before the implementation of the programme, while a post-test survey was carried out about 18 months after the pre-test. The association between programme condition and change in substance use at post-test was expressed as adjusted prevalence odds ratio (POR), estimated by multilevel regression models.
Persisting beneficial programme effects were found for episodes of drunkenness (any, POR=0.80; 0.67–0.97; frequent, POR=0.62; 0.47–0.81) and for frequent cannabis use in the past 30 days (POR=0.74; 0.53–1.00), whereas daily cigarette smoking was not affected by the programme as it was at the short-term follow-up. Baseline non-smokers that participated in the programme progressed in tobacco consumption to a lower extent than those in the control condition, but no difference was detected in the proportion of quitters or reducers among baseline daily smokers.
The study concludes that the experimental evaluation of an innovative school curriculum based on a comprehensive social influence approach, indicated persistent positive effects over 18 months for reducing alcohol  and for cannabis use, but not for cigarette smoking.
The project report is available from www.eudap.net/PDF/FinalReport2.pdf