Impact of Anti-drug Use Advertisements in Hong Kong: A Randomized Control Experiment

Background: This study examined how anti-drug use advertisements, along with perceptions of their realism and threat to personal freedom, impact perceptions toward drug use among Chinese university students in Hong Kong. Despite the widespread use of such ads globally, their potential for a “boomerang effect” has been understudied outside Western contexts. Methods: 483 students (aged 18–25) were randomly assigned to view either anti-drug or unrelated advertisements. Pre- and post-intervention surveys assessed their perceptions. Data were analyzed using two-tailed t-tests, a two-way mixed ANOVA, and ordinary least squares regression models. Results: No boomerang effect was found; exposure to anti-drug ads had limited influence on drug use perceptions. Unrealistic ads were associated with more favorable perceptions of drug use, while perceived threat to personal freedom did not significantly impact perceptions. Conclusion: Cultural context may influence the boomerang effect. Anti-drug campaigns should use coherent, realistic narratives to effectively promote negative drug views.