Self-Guided Online Program Helps Cannabis Users Meet Their Reduction Goals in Two Weeks | Research

The takeaway

A two-week online self-guided intervention using mental contrasting with implementation intentions helped 69% of participants meet their cannabis reduction goals, compared to 49% in the control group, with reductions maintained at three months.

Cannabis users wanting to cut back, clinicians looking for self-help tools, and digital health researchers.

69% of the MCII group met their cannabis reduction goals

What the researchers found

The MCII group achieved objective reduction goals at 69%, vs. 49% for control (SMART goals alone). Adding cue-control did not improve outcomes (60%). All groups reduced grams per week, maintained at 3-month follow-up. Two-week retention was high in the MCII group.

Why it matters

Many cannabis users prefer self-help over formal treatment. This brief, accessible online program can meaningfully help people meet their own reduction goals.

The numbers in context

168 participants; 69% MCII group met goals vs. 49% control; 60% MCII + cue-control; reductions maintained at 3 months.

How the study worked

Pilot RCT with 168 adults using cannabis weekly (severe CUD on average). Three conditions: SMART goals only, SMART + MCII, SMART + MCII + cue-control. Two-week primary endpoint with 3-month follow-up.

What this study cannot tell us

Pilot/feasibility scale. No blinding. All groups reduced use. Grams per week reduction was similar across groups despite goal achievement differences.

How to read the evidence

Randomized design with meaningful effect sizes, but pilot scale and lack of blinding limit evidence strength.

When this study was published

2025 pilot feasibility RCT with 3-month follow-up.

The bigger picture

Self-guided digital interventions could fill a major gap in cannabis treatment, reaching the large population of users who would never enter a clinic.

Questions still open

Why did cue-control not add benefit?
Would a larger trial confirm these results?

Common questions

Can you reduce cannabis use without formal treatment?

This study suggests a brief self-guided online program can help many weekly cannabis users meet their own reduction targets.

What is MCII?

Mental contrasting with implementation intentions: you imagine your goal, contrast it with obstacles, and create if-then plans. It outperformed goal-setting alone.

Read the original research

Back on track: Feasibility and efficacy randomized trial of a two-week online self-guided intervention for cannabis use reduction.

Drug and alcohol dependence, 277, 112943

View on PubMed ↗Publisher’s paper ↗

Citation

Kroon, E; Elsey, J W B; Kuhns, L N; Rietveld, P; De Vries, O; Larsen, H; Wiers, R W H J; Cousijn, J. (2025). Back on track: Feasibility and efficacy randomized trial of a two-week online self-guided intervention for cannabis use reduction.. Drug and alcohol dependence, 277, 112943. https://doi.org/10.1016/j.drugalcdep.2025.112943