"Effects of the National Youth Anti-Drug Media Campaign on Youths." American Journal of Public Health, 2008.

Robert Hornik, Lela Jacobsohn, Robert Orwin, Andrea Piesse, and Graham Kalton

Objectives. We examined the cognitive and behavioral effects of the National Youth Anti-Drug Media Campaign on youths aged 12.5 to 18 years and report core evaluation results.

Methods. From September 1999 to June 2004, 3 nationally representative cohorts of US youths aged 9 to 18 years were surveyed at home 4 times. Sample size ranged from 8117 in the first to 5126 in the fourth round (65% first-round response rate, with 86%–93% of still eligible youths interviewed subsequently). Main outcomes were self-reported lifetime, past-year, and past-30-day marijuana use and related cognitions.

Results. Most analyses showed no effects from the campaign. At one round, however, more ad exposure predicted less intention to avoid marijuana use (γ = −0.07; 95% confidence interval [CI] = −0.13, −0.01) and weaker antidrug social norms (γ = −0.05; 95% CI = −0.08, −0.02) at the subsequent round. Exposure at round 3 predicted marijuana initiation at round 4 (γ = 0.11; 95% CI = 0.00, 0.22).

Conclusions. Through June 2004, the campaign is unlikely to have had favorable effects on youths and may have had delayed unfavorable effects. The evaluation challenges the usefulness of the campaign.