Personality-targeted school program reduced cannabis-related harms over 7 years

The PreVenture group had 22% lower odds of annual cannabis-related harms compared to controls (OR=0.78, 95% CI: 0.65-0.92). However, there were no significant differences in cannabis use (OR=0.84, 95% CI: 0.69-1.02) or stimulant use (OR=1.07, 95% CI: 0.91-1.25) growth over the 7-year period.

Cluster randomized controlled trial in 14 Australian schools. High-risk students (scoring high on anxiety sensitivity, negative thinking, impulsivity, or sensation seeking) received PreVenture (two 90-minute sessions one week apart) or usual health education. Outcomes tracked from baseline through 7 years post-intervention.

Most drug prevention programs show only short-term effects. Finding that a brief, two-session intervention reduced cannabis harms over 7 years into early adulthood is notable, even though it did not reduce use itself. Reducing harms without eliminating use aligns with harm reduction approaches.

Personality-targeted prevention is a growing field that matches interventions to individual risk profiles rather than using one-size-fits-all approaches. This 7-year result suggests that even brief, targeted interventions during adolescence can have lasting protective effects on how people experience cannabis consequences.

Substantial attrition over 7 years (retention as low as 51%). The intervention did not reduce cannabis or stimulant use rates. Only high-risk students were included, limiting generalizability. Australian context may differ from other countries.