A tailored web-based program helped young adults reduce their cannabis use | Research

The takeaway

A web-based intervention tailored to individual risk profiles reduced cannabis use in 10.8% of participants versus 5.1% in the control group, with significant improvement in intention to abstain.

Read this if you are a young adult looking for low-key ways to reduce your cannabis use.

10.8% reduced cannabis use with the intervention vs 5.1% without

What the researchers found

Researchers tested a theory-based, web-tailored intervention to reduce cannabis use among 588 young adults (ages 18-24) attending adult education centers in Quebec. Participants were randomly assigned to receive the intervention or serve as controls.

Among the 343 participants who had used cannabis in the past year, 10.8% in the experimental group reduced their use at follow-up compared to only 5.1% in the control group, a statistically significant difference.

The intervention also significantly increased intention to abstain from cannabis in the coming month. While the control group's intention remained stable, the experimental group showed a meaningful increase, suggesting the program successfully shifted attitudes and planned behavior.

The intervention was grounded in motivational interviewing and cognitive behavioral principles, with content tailored to each participant's risk profile, use patterns, and readiness to change.

Why it matters

Young adults who use cannabis frequently are often difficult to reach through traditional treatment programs. Web-based interventions can be delivered at scale, at low cost, and without the stigma associated with formal treatment. This study demonstrates that even a brief tailored online program can produce measurable reductions in cannabis use.

The numbers in context

588 participants randomized (295 experimental, 293 control). 343 reported past-year cannabis use. Cannabis use reduction: 10.8% experimental vs 5.1% control (chi-squared = 9.89, p = 0.007). Intention to abstain: increased in experimental group (5.07 to 5.45), stable in controls (5.32 to 5.36; interaction p = 0.005).

How the study worked

Randomized controlled trial with 588 young adults (18-24 years) from adult education centers in Quebec. Participants were randomly assigned to a web-based tailored intervention or control group. Cannabis use (primary outcome) and intention to abstain (secondary outcome) were assessed at baseline and post-intervention. Intention-to-treat analysis was used.

What this study cannot tell us

The follow-up period was short, and it is unclear if reductions were sustained. The effect size was modest (about 6 percentage point difference). Self-reported cannabis use may be unreliable. The study was conducted in Quebec adult education centers, which may not represent all young adult populations. Attrition rates were not detailed.

How to read the evidence

This is a randomized controlled trial with appropriate analysis, providing moderate evidence for a modest but significant intervention effect.

When this study was published

Published in 2018. Web-based cannabis reduction programs have continued to develop.

The bigger picture

As cannabis becomes more accessible, low-threshold interventions for young adults who want to reduce but not necessarily eliminate their use become increasingly important. Web-based tools can serve as a first step in the care continuum, reaching people who would not seek formal treatment.

Questions still open

Are the cannabis use reductions sustained over longer periods? Could the program be enhanced by adding human support or follow-up contacts? Would the intervention be equally effective in recreational versus medical cannabis users?

Common questions

Can an online program help me use less cannabis?

This study found that a tailored web-based program helped about twice as many young adults reduce their cannabis use compared to no intervention (10.8% vs 5.1%). The program also increased motivation to abstain.

How does the program work?

The web-based intervention was tailored to each person's use patterns and readiness to change, using principles from motivational interviewing and cognitive behavioral therapy. The personalized approach appeared to be more effective than general information.

Read the original research

Efficacy of a Web-Based Tailored Intervention to Reduce Cannabis Use Among Young People Attending Adult Education Centers in Quebec.

Telemedicine journal and e-health : the official journal of the American Telemedicine Association, 24(11), 853-860

View on PubMed ↗Publisher’s paper ↗

Citation

Côté, José; Tessier, Sébastien; Gagnon, Hélène; April, Nicole; Rouleau, Geneviève; Chagnon, Miguel. (2018). Efficacy of a Web-Based Tailored Intervention to Reduce Cannabis Use Among Young People Attending Adult Education Centers in Quebec.. Telemedicine journal and e-health : the official journal of the American Telemedicine Association, 24(11), 853-860. https://doi.org/10.1089/tmj.2017.0144