"The community treatment parameter estimate was significant (?=?0.51, p=0.026), indicating that community-level treatment lowered the propensity to use marijuana at the last measurement occasion over and above the effect of the 'Above the Influence' campaign. There was no evidence that school-level treatment affected the marijuana use at the last measurement occasion. Neither the community-level nor the school-level treatment for the 'Be Under Your Own Influence' campaign provided evidence of an effect on the linear rate-of-change for marijuana use.

"The extent of exposure to the ONDCP 'Above the Influence' campaign (RQ1) was assessed by cross-tabulating the measures of self-reported exposure to this campaign with each of the four treatment/control cells at the fourth wave of data collection, the point by which such exposure would have taken place for all study participants. Of youth in the control community/control school cell, 73% said they definitely had seen the ONDCP 'Above the Influence' campaign. The self-reported exposure to the ONDCP campaign was similar in the three treatment cells (68–79%).

"Westat's analysis of the relationship between exposure to campaign advertisements and youth self-reported drug use in the NSPY [National Survey of Parents and Youth] data for the entire period covered by its evaluation -- assessments that used statistical methods to adjust for individual differences and control for other factors that could explain changes in self-reported drug use -- showed no significant effects of exposure to the campaign on initiation of marijuana by prior nonusing youth.