title: The influence of socioeconomic environment on the effectiveness of alcohol prevention among European students: a cluster randomized controlled trial.
abstract: BACKGROUND
  Although social environments may influence alcohol-related behaviours in youth, the relationship between neighbourhood socioeconomic context and effectiveness of school-based prevention against underage drinking has been insufficiently investigated. We study whether the social environment affects the impact of a new school-based prevention programme on alcohol use among European students.
  
  
  METHODS
  During the school year 2004-2005, 7079 students 12-14 years of age from 143 schools in nine European centres participated in this cluster randomised controlled trial. Schools were randomly assigned to either control or a 12-session standardised curriculum based on the comprehensive social influence model. Randomisation was blocked within socioeconomic levels of the school environment. Alcohol use and alcohol-related problem behaviours were investigated through a self-completed anonymous questionnaire at baseline and 18 months thereafter. Data were analysed using multilevel models, separately by socioeconomic level.
  
  
  RESULTS
  At baseline, adolescents in schools 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, although the estimates did not attain statistical significance in any subgroup.
  
  
  CONCLUSIONS
  It is plausible that comprehensive social influence programmes have a more favourable effect on problematic drinking among students in underprivileged social environments.
  
  
  BACKGROUND
  ISRCTN: ISRCTN18092805.
authors.affiliation: Department of Public Health Sciences, Karolinska Institutet, Norrbacka, SE-171 76 Stockholm, Sweden. maria.paola.caria@ki.se
authors.forename: Maria Paola
authors.initials: MP
authors.lastname: Caria
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Faggiano
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Galanti
mesh_terms: D000293:Adolescent; D000435:Alcoholic Intoxication / Q000517:prevention & control*; D002648:Child; D005060:Europe; D006801:Humans; D015397:Program Evaluation; D012923:Social Class; D013334:Students; D011795:Surveys and Questionnaires