Background High quality evaluation studies of school-based programs against substance abuse are quite rare. A recent Cochrane review pointed out that most studies do not follow the criteria for a rigorous evaluation, and most of those having high quality have been conducted in North America. The EU-Dap project was funded by the European Commission in 2002 to cover the lack of European studies. The evaluation study was designed as a multicentric cluster randomized controlled trial. Methods The “Unplugged” program, based on a Comprehensive Social Influence approach and consisting of 12 one-hour sessions delivered by class teachers, was implemented in seven European countries during the 2004-2005 school year. One hundred and forty-three schools (7th, 8th and 9th grade) were randomised into three intervention arms (basic curriculum, basic plus peer involvement and basic plus parent involvement), and a usual curriculum control arm. A pre-test survey was conducted before the implementation of the program (n=7079), while two post-test surveys were conducted afterwards, the first 3 months after the end of the program (n=6370), and the second at 1 year follow-up (n=5541). Multilevel Analysis was used to investigate the effectiveness of the program in preventing and reducing drug use at the post test and at one year follow-up. Results At the post-test, the program was effective in reducing the prevalence of use in the last 30 days for all the analysed variables. The Prevalence Odds Ratios of use were 0.70 (0.52-0.94) for daily smoking (>20 cigarettes in the last 30 days), 0.72 (0.58-0.90) for sporadic drunkenness (at least once in the last 30 days), 0.69 (0.48-0.99) for regular drunkenness (>3 times) and 0.77 (0.60-1.00) for sporadic use of cannabis (at least once). At one year follow-up, the effectiveness on cigarettes use was not statistically significant anymore, while the effect on drunkenness episodes was maintained, with a Prevalence Odds Ratio of 0.80 (0.67-0.97) for sporadic drunkenness and of 0.62 (0.47-0.81) for regular drunkenness. The effect on cannabis use was slightly significant, with a POR of 0.74 (0.53-1.01) for regular use (>3 times in the last 30 days). A significant program*sex interaction was detected, with boys showing high responsiveness (POR for regular smoking 0.68, 95%CI: 0.50-0.93; for daily smoking 0.49, 95%CI: 0.34-0.71; for cannabis use 0.62, 95%CI: 0.45-0.85; for all drugs use 0.64, 95%CI: 0.48-0.86), while the effect was not detected among girls (POR for regular smoking 1.07, 95%CI: 0.74-1.55; for daily smoking 0.99, 95%CI: 0.64-1.52; for cannabis use 1.05, 95%CI: 0.70-1.58; for all drugs use 1.40, 95%CI: 0.95-2.04). This pattern was constant across all substance use and across geographical locations. Conclusions The EU-Dap project is the first large European evaluation of a comprehensive drug prevention program for adolescents. At the post test, it reduces of 25-30% the daily use of cigarettes, sporadic and regular drunkenness and sporadic use of cannabis. At one year follow-up, it reduces of 20% sporadic drunkenness episodes and of 40% the regular ones and it is likely to reduce of 25% regular use of cannabis. However, gender differences were detected, with a strong program effect on males and apparently no effect on females. Possible interpretations include: differential stages of use at the time of prevention or specific gender sensitivity of the underlying pedagogic models in modern prevention. The findings highlight the importance of studying sex differences in prevention research.
The EU-Dap cluster randomized controlled trial: evaluation of effectiveness of an European school-based program for drug use prevention among adolescents
VIGNA-TAGLIANTI, Federica;SILIQUINI, Roberta;
2008-01-01
Abstract
Background High quality evaluation studies of school-based programs against substance abuse are quite rare. A recent Cochrane review pointed out that most studies do not follow the criteria for a rigorous evaluation, and most of those having high quality have been conducted in North America. The EU-Dap project was funded by the European Commission in 2002 to cover the lack of European studies. The evaluation study was designed as a multicentric cluster randomized controlled trial. Methods The “Unplugged” program, based on a Comprehensive Social Influence approach and consisting of 12 one-hour sessions delivered by class teachers, was implemented in seven European countries during the 2004-2005 school year. One hundred and forty-three schools (7th, 8th and 9th grade) were randomised into three intervention arms (basic curriculum, basic plus peer involvement and basic plus parent involvement), and a usual curriculum control arm. A pre-test survey was conducted before the implementation of the program (n=7079), while two post-test surveys were conducted afterwards, the first 3 months after the end of the program (n=6370), and the second at 1 year follow-up (n=5541). Multilevel Analysis was used to investigate the effectiveness of the program in preventing and reducing drug use at the post test and at one year follow-up. Results At the post-test, the program was effective in reducing the prevalence of use in the last 30 days for all the analysed variables. The Prevalence Odds Ratios of use were 0.70 (0.52-0.94) for daily smoking (>20 cigarettes in the last 30 days), 0.72 (0.58-0.90) for sporadic drunkenness (at least once in the last 30 days), 0.69 (0.48-0.99) for regular drunkenness (>3 times) and 0.77 (0.60-1.00) for sporadic use of cannabis (at least once). At one year follow-up, the effectiveness on cigarettes use was not statistically significant anymore, while the effect on drunkenness episodes was maintained, with a Prevalence Odds Ratio of 0.80 (0.67-0.97) for sporadic drunkenness and of 0.62 (0.47-0.81) for regular drunkenness. The effect on cannabis use was slightly significant, with a POR of 0.74 (0.53-1.01) for regular use (>3 times in the last 30 days). A significant program*sex interaction was detected, with boys showing high responsiveness (POR for regular smoking 0.68, 95%CI: 0.50-0.93; for daily smoking 0.49, 95%CI: 0.34-0.71; for cannabis use 0.62, 95%CI: 0.45-0.85; for all drugs use 0.64, 95%CI: 0.48-0.86), while the effect was not detected among girls (POR for regular smoking 1.07, 95%CI: 0.74-1.55; for daily smoking 0.99, 95%CI: 0.64-1.52; for cannabis use 1.05, 95%CI: 0.70-1.58; for all drugs use 1.40, 95%CI: 0.95-2.04). This pattern was constant across all substance use and across geographical locations. Conclusions The EU-Dap project is the first large European evaluation of a comprehensive drug prevention program for adolescents. At the post test, it reduces of 25-30% the daily use of cigarettes, sporadic and regular drunkenness and sporadic use of cannabis. At one year follow-up, it reduces of 20% sporadic drunkenness episodes and of 40% the regular ones and it is likely to reduce of 25% regular use of cannabis. However, gender differences were detected, with a strong program effect on males and apparently no effect on females. Possible interpretations include: differential stages of use at the time of prevention or specific gender sensitivity of the underlying pedagogic models in modern prevention. The findings highlight the importance of studying sex differences in prevention research.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
