A digital harm reduction app was feasible and acceptable for young adults with first-episode psychosis who use cannabis | Research

The takeaway

The CHAMPS digital harm reduction app showed 82% trial retention and 59% completion among young adults with first-episode psychosis, with signals of improvement in harm reduction strategy use and cannabis-related problems.

Early intervention psychosis clinicians, digital health researchers, and harm reduction practitioners.

82% retention, 59% completion

What the researchers found

Trial retention was 82.2% and CHAMPS completion rate was 58.8%, meeting pre-specified thresholds for feasibility and acceptability. Signals of possible improvement were observed in harm reduction strategy use, motivation to change cannabis behaviors, cannabis-related problems, and cannabis use frequency in the intervention group.

Why it matters

Cannabis use worsens prognosis for people with first-episode psychosis, but many are not ready for abstinence-focused treatment. Harm reduction approaches that meet patients where they are could improve outcomes for this vulnerable population.

The numbers in context

N = 101 young adults (ages 18-35) with FEP. Retention: 82.2% (threshold: 60%). Completion: 58.8% (threshold: 50%). Six-module digital intervention. Assessments at baseline, weeks 6, 12, 18.

How the study worked

Multi-site pilot randomized controlled trial comparing early intervention services (EIS) + CHAMPS digital app versus EIS-only in 101 young adults aged 18-35 with first-episode psychosis who use cannabis. Outcomes assessed at baseline and weeks 6, 12, and 18.

What this study cannot tell us

Pilot study not powered for efficacy. Improvement signals are preliminary and require confirmation. Cannabis use was self-reported. Multi-site design adds generalizability but also variability.

How to read the evidence

Well-designed multi-site pilot RCT meeting feasibility and acceptability thresholds, but underpowered for efficacy conclusions.

When this study was published

2025 publication

The bigger picture

This study represents an important philosophical shift in psychosis care: rather than requiring cannabis abstinence as a prerequisite for treatment, harm reduction accepts current use while working to minimize its negative consequences.

Questions still open

Will the signals of improvement hold in a fully powered efficacy trial? Can CHAMPS be integrated into standard early intervention services? Would combining CHAMPS with clinical support improve outcomes further?

Common questions

What is CHAMPS?

Cannabis Harm-reducing App to Manage Practices Safely, a six-module digital intervention designed for young adults with first-episode psychosis who use cannabis but are not ready for abstinence-focused treatment.

Did the app reduce cannabis use in people with psychosis?

There were preliminary signals of improvement in harm reduction strategy use, motivation to change, cannabis-related problems, and use frequency, but the study was designed to test feasibility, not efficacy. A larger trial is needed to confirm benefits.

Read the original research

A pilot randomized controlled trial of a digital cannabis harm reduction intervention for young adults with first-episode psychosis who use cannabis.

Psychiatry research, 350, 116553

View on PubMed ↗Publisher’s paper ↗

Citation

Coronado-Montoya, Stephanie; Abdel-Baki, Amal; Bodson-Clermont, Paule; Boucher-Roy, David; Côté, José; Crocker, Candice E; Crockford, David; Daneault, Jean-Gabriel; Dubreucq, Simon; Dussault-Laurendeau, Maxime; Fischer, Benedikt; Lachance-Touchette, Pamela; Lecomte, Tania; L'Heureux, Sophie; Ouellet-Plamondon, Clairélaine; Roy, Marc-André; Tatar, Ovidiu; Tibbo, Philip G; Villeneuve, Marie; Wittevrongel, Anne; Jutras-Aswad, Didier. (2025). A pilot randomized controlled trial of a digital cannabis harm reduction intervention for young adults with first-episode psychosis who use cannabis.. Psychiatry research, 350, 116553. https://doi.org/10.1016/j.psychres.2025.116553