Home > Review of the evidence base in drug prevention.

Keane, Martin (2009) Review of the evidence base in drug prevention. Drugnet Ireland, Issue 29, Spring 2009, p. 12.

PDF (Drugnet Ireland, issue 29) - Published Version

This article summarises the main conclusions drawn in a recent review of the evidence base in substance abuse prevention published by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA).1 It will focus in particular on family- and school-based prevention as these are important areas of intervention in Ireland's National Drugs Strategy.

The review included 49 studies, including eight meta-analyses, 22 systematic reviews, 13 unsystematic reviews, four best-practice surveys and two other publications. These studies were systematically identified from searches of established databases, e.g. the Cochrane Library, PubMed and PsychInfo. Two assessors independently rated the studies by content and method using a coding system. They then jointly formulated their conclusions and rated them for strength of evidence from A to F, according to whether they were based on:
A - a meta-analysis involving high-quality studies
B - a systematic review involving high-quality studies
C - a meta-analysis or systematic review covering all relevant studies
D - an unsystematic review
E - a discussion or an individual study or conclusion on the basis of empirical results
F - a contradictory body of evidence from reviews in different categories.
Family-based prevention: conclusions from the evidence base
What works
Comprehensive family-orientated approaches (training for parents, children and families) have preventive effects on consumption behaviour in relation to alcohol. The studies included did not focus on preventing illicit drug use.
Family-orientated measures are particularly effective with non-consumers (of alcohol), particularly the parents.
 Parental training alone can influence risk factors (increasing pro-social behaviour) but not consumption of substances.
How it works
Parental training includes a focus on developing basic educational behaviour (use of discipline, supervision and problem-solving techniques) and on fostering parent-child relationships, as well as on parental commitment to the child's schooling.
 Training involving children teaches ways to resist peer offers of substances for consumption, social problem-solving abilities, conflict management and learning skills.
Engaging hard-to-reach families
Measures to involve hard-to-reach families appear successful (Strategic Structural Systems Engagement approach)
Strength of evidence for family-based prevention
Rated C and D. While there were numerous random controlled trials included in the reviews, there were no reviews of high-quality studies and no meta-analyses.
School-based prevention: conclusions from the evidence base
What works
Interactive school-based programmes have preventive effects on consumption behaviour for tobacco, alcohol, cannabis and other illicit drugs.
School-based programmes that implement the concepts of social influence and life skills are effective, and equally so for all substances.
Effects with regard to alcohol and tobacco can be long term (2-3 years)
 School-based prevention programmes have less effect on consumption behaviour than they do on risk factors such as dropping out of school, truancy and other problem behaviour.
 Short-term effects are a good pointer to long-term effectiveness.
What does not work
Non-interactive programmes are not effective; such programmes include information provision alone, emotional education alone, transmission of values and decision-making alone and DARE-type programmes (delivered didactically by police officers in the United States).
 Strength of evidence for school-based prevention
Rated A to C. The report reviewed numerous meta-analyses including high-quality studies.
Disseminating information on what works in drug prevention is an important field of interest for the EMCDDA. Currently this work is done through the best practice portal of the EMCDDA2 where a number of reviews are stored.  The Alcohol and Drug Research Unit of the Health Research Board (HRB), as the Focal Point for the EMCDDA in Ireland, is committed to summarising these reviews for the benefit of our stakeholders in Ireland and disseminating this information. Commentary on a review of the evidence base for selective prevention targeting high-risk groups will be covered in a future issue of Drugnet Ireland.
1. Bühler A and Kröger C (2008) EMCDDA Insights: Prevention of substance abuse. Luxembourg: Office for Official Publications of the European Communities. First published in German in 2006 as Expertise zur Prävention des Substanzmißbrauchs by the Federal Centre for Health Education and subsequently translated into English by the EMCDDA.
2. http://www.emcdda.europa.eu/themes/best-practice

Repository Staff Only: item control page