title: A cross-validation trial of an Internet-based prevention program for alcohol and cannabis: Preliminary results from a cluster randomised controlled trial.
abstract: OBJECTIVE
  Replication is an important step in evaluating evidence-based preventive interventions and is crucial for establishing the generalizability and wider impact of a program. Despite this, few replications have occurred in the prevention science field. This study aims to fill this gap by conducting a cross-validation trial of the Climate Schools: Alcohol and Cannabis course, an Internet-based prevention program, among a new cohort of Australian students.
  
  
  METHODS
  A cluster randomized controlled trial was conducted among 1103 students (Mage: 13.25 years) from 13 schools in Australia in 2012. Six schools received the Climate Schools course and 7 schools were randomized to a control group (health education as usual). All students completed a self-report survey at baseline and immediately post-intervention. Mixed-effects regressions were conducted for all outcome variables. Outcomes assessed included alcohol and cannabis use, knowledge and intentions to use these substances.
  
  
  RESULTS
  Compared to the control group, immediately post-intervention the intervention group reported significantly greater alcohol (d = 0.67) and cannabis knowledge (d = 0.72), were less likely to have consumed any alcohol (even a sip or taste) in the past 6 months (odds ratio = 0.69) and were less likely to intend on using alcohol in the future (odds ratio = 0.62). However, there were no effects for binge drinking, cannabis use or intentions to use cannabis.
  
  
  CONCLUSIONS
  These preliminary results provide some support for the Internet-based Climate Schools: Alcohol and Cannabis course as a feasible way of delivering alcohol and cannabis prevention. Intervention effects for alcohol and cannabis knowledge were consistent with results from the original trial; however, analyses of longer-term follow-up data are needed to provide a clearer indication of the efficacy of the intervention, particularly in relation to behavioral changes.
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia k.champion@unsw.edu.au.
authors: Katrina E
authors: KE
authors: Champion
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
authors: Nicola C
authors: NC
authors: Newton
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
authors: Lexine
authors: L
authors: Stapinski
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
authors: Tim
authors: T
authors: Slade
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
authors: Emma L
authors: EL
authors: Barrett
authors: NHMRC Centre of Research Excellence in Mental Health and Substance Use, National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW, Australia.
authors: Maree
authors: M
authors: Teesson
mesh_terms: D000293:Adolescent; D063425:Binge Drinking / Q000517:prevention & control*; D002648:Child; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D033182:Intention; D020407:Internet; D008297:Male; D008385:Marijuana Smoking / Q000517:prevention & control*; D012572:School Health Services; D013813:Therapy, Computer-Assisted; D000066608:Underage Drinking / Q000517:prevention & control*
keywords: Alcohol; Internet; cannabis; prevention; replication; school-based