An Alternative Framework for Defining Mediation

Outcome research has shown that drug prevention programs based on theories of social influence often prevent the onset of adolescent drug use. However, little is known empirically about the processes through which they have their effects. The purpose of the present study was to evaluate intervening mechanism theories of two program models for preventing the onset of adolescent drug use. Analyses based on a total of 3077 fifth graders participating in the Adolescent Alcohol Prevention Trial revealed that both normative education and resistance training activated the causal processes they targeted. While beliefs about prevalence and acceptability significantly mediated the effects of normative education on subsequent adolescent drug use, resistance skills did not significantly predict subsequent drug use. More impressively, this pattern of results was virtually the same across sex, ethnicity, context (public versus private school students), drugs (alcohol, cigarettes, and marijuana) and levels of risk and was durable across time. These findings strongly suggest that successful social influence-based prevention programs may be driven primarily by their ability to foster social norms that reduce an adolescent's social motivation to begin using alcohol, cigarettes, and marijuana.

Recent research suggests that the success of social influence prevention programs is due to enhancing an adolescent's ability to resist passive social pressure (e.g., social modeling and overestimation of peer use), and is not due to teaching refusal skills for combating active social pressure (i.e., alcohol and drug offers). Using 4 waves of longitudinal data (collected in the 5th, 6th, 7th, and 8th grades) from 11,995 students participating in the Adolescent Alcohol Prevention Trial, resistance-skills training was found to be an effective strategy for preventing the onset of alcohol use when program assumptions were met. However, a counterproductive effect was found for adolescents attending public school who received a resistance training only condition.