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Effect of early, brief computerized interventions on risky alcohol and cannabis use among young people

Additional Info

  • Authors: Geir Smedslund, Sabine Wollscheid, Lin Fang, Wendy Nilsen, Asbjørn Steiro, Lillebeth Larun
  • Published date: 2017-04-07
  • Coordinating group(s): Social Welfare
  • Type of document: Title, Protocol, Review, Plain language summary
  • See the full review:

About this systematic review

This Campbell systematic review examines research on the effectiveness of early, computerized brief interventions on alcohol and cannabis use by young people who are high or risky consumers of either one or both of these substances. The review summarises findings from 60 studies from 10 countries. The participants were young people between the ages of 15 and 25, defined as risky consumers of alcohol or cannabis or both. The review included 33,316 participants.

What are the main results?

The interventions significantly reduce alcohol consumption in the short-term compared to no intervention, but the effect size is small, and there is no significant effect in the long-term. There are also shortcomings in the quality of the evidence.

Interventions which provide an assessment of alcohol use with feedback may have a larger effect that those which do not, but again, the evidence is weak.

The few studies on cannabis did not show significant effects in the reduction of cannabis consumption.

There was no evidence of adverse effects.


Young people’s risky use of alcohol or recreational drugs, such as cannabis, remains a significant public health issue. Many countries have made substantial efforts to minimize the long-term consequences of alcohol and/or cannabis use at multiple levels, ranging from government policy initiatives to primary health care services.

In this review, we focused on the effects of brief interventions, provided by electronic devices (computerized brief interventions). A brief intervention is defined as any preventive or therapeutic activity delivered by a health worker, psychologist, social worker, or volunteer worker, and given within a maximum of four structured therapy sessions each lasting between five and ten minutes with a maximum total time of one hour. Brief interventions may work by making the clients think differently about their alcohol/cannabis use, and by providing them with skills to change their behavior if they are motivated to change.

A computerized brief intervention, in contrast, is not directly delivered by a human being, but may be delivered through online and offline electronic devices. Such interventions can reach large audiences at a low cost and can simultaneously simulate an ‘interpersonal therapeutic component’ by targeting recipients’ feedback.


To assess the effectiveness of early, computerized brief interventions on alcohol and cannabis use by young people aged 15 to 25 years who are high or risky consumers of either one or both of these substances by synthesizing data from randomized controlled trials.

Search methods

We searched 11 electronic databases including MEDLINE, PsycINFO, EMBASE, Cinahl and The Cochrane Library in April 2016 for published, unpublished and ongoing studies using adapted subject headings and a comprehensive list of free-text terms. Additionally, we searched the reference lists of the included studies. We also have set up an EBSCO host alert notification ([email protected]) that continuously surveys the Cochrane Library (including CENTRAL), Medline and Embase. We receive updated searches via email. This search is up to date as of May 2016.

Selection criteria

We included all randomized or quasi-randomized controlled trials of any computerized brief intervention used as a stand-alone treatment aimed at reducing alcohol and/or cannabis consumption. Eligible comparators included no intervention, waiting list control or an alternative brief intervention (computerized or non-computerized). Participants were young people between 15 and 25 years of age who were defined as risky consumers of alcohol or cannabis, or both.

Data collection and analysis

Two researchers independently screened titles and abstracts against the inclusion criteria. Two researchers independently assessed the full texts of all included articles. We used standard methodological procedures expected by the Campbell Collaboration.


We included 60 studies that had randomized 33,316 participants in this review. Study characteristics: The studies were mostly from the United States and targeted high and risky alcohol use among university students. Bias/quality assessment: Some of the studies lacked clear descriptions of how the randomization sequence was generated and concealed. Many of the studies did not blind the participants. Some of the studies suffered from high loss to follow-up, and few studies had a pre-registered protocol. Findings: For alcohol, we found moderate quality evidence that multi-dose assessment and feedback was more effective than a single-dose assessment. We found low quality evidence that assessment and feedback might be more effective than no intervention. Assessment and feedback might also be more effective than assessment alone (low quality evidence). Short-term effects (< 6 months) were mostly larger than long-term (≥6 months) effects. For cannabis, we found that assessment and feedback might slightly reduce short-term consumption compared to no intervention. Adding feedback to assessment may have little or no effect on short-term cannabis consumption. Moreover, there may be little or no difference between assessment plus feedback and education on short-term and long-term cannabis consumption. Adverse effects: We did not find evidence of any adverse effects of the interventions.

Implications for policy, practice and research

Computerized brief interventions are easy to administer, and the evidence from this review indicates that such brief interventions might reduce drinking for several months after the intervention. Additionally, there is no evidence for adverse effects. This means that brief, computerized interventions could be feasible ways of dealing with risky alcohol use among young people. The evidence on cannabis consumption is scarcer, suggesting the need for more research.

See the full review

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