Does harm minimisation lead to greater experimentation? Results from a school smoking intervention trial

Declines in adolescent smoking prevalence have slowed recently, resulting in increased interest and literature in tobacco harm minimisation. To date, harm reduction strategies have focused largely on modifying the product and alternative (safer) mechanisms of nicotine delivery. There has been little exploration of primary harm minimisation to prevent the onset of regular smoking among young people. A major concern expressed about harm reduction interventions and young people is that they may increase experimentation among non-users.

The Smoking Cessation for Youth Project was a 2-year school-based cluster randomised controlled trial conducted in 30 Western Australian schools. Results on the primary outcome showed a significant reduction in regular smoking among 4636 13-15-year-olds receiving a harm minimisaton versus standard intervention. This paper addresses the intervention effects on 2078 students who had not smoked at baseline.

At 20-month follow-up, smoking initiation was slightly lower among intervention students than comparison students (who received a largely abstinence-based intervention), although this difference did not attain statistical significance (OR=0.86; 95% confidence interval: 0.68, 1.09).

This study provided limited evidence to suggest that harm minimisation is a superior approach to abstinence-based interventions for non-smokers. However, this intervention did not contribute to increased experimentation among non-smokers. Although more trials are required, these results indicate that fears of potential negative iatrogenic effects from school-based harm minimisation interventions may be unwarranted.