Can school-based prevention programs reduce health inequalities? The example of Unplugged, from research to practice

Despite the potential high impact of prevention programs in reducing health inequalities, this question has received little attention in intervention research. The aim of this study was to evaluate whether the social environment modifies the impact of a preventive school curriculum (Unplugged) program on students’ alcohol use. During the school year 2004-2005, 143 schools (7079 pupils) of seven European countries were randomly assigned to either control or a 12-session curriculum based on a social influence model. Randomisation was blocked within socioeconomic levels of the school environment. Alcohol use and alcohol-related problem behaviours were investigated at baseline and 18 months thereafter. Data was analysed using multilevel regression modelling. At baseline, adolescents from schools located in neighbourhoods of low socioeconomic level were more likely to report problem drinking than other students. Participation in the programme was associated in this group with a decreased odds of reporting episodes of drunkenness (OR = 0.60, 95% CI = 0.44-0.83), intention to get drunk (OR = 0.60, 95% CI = 0.45-0.79), and marginally alcohol-related problem behaviours (OR = 0.70, 95% CI = 0.46-1.06). No significant programme’s effects emerged for students in schools of medium or high socioeconomic level. Effects on frequency of alcohol consumption were also stronger among students in disadvantaged schools. Comprehensive social influence school-based curricula may have a more favourable effect on problematic drinking among students in underprivileged social environments. If administered in unselected populations, they can contribute to reduce inequalities in risk factors for ill-health.