Project TND: A School Program That Consistently Reduced Hard Drug Use Across Seven Trials | Research

The takeaway

Across seven randomized controlled trials, Project Towards No Drug Abuse consistently reduced hard drug use, with effects on alcohol in four trials, and on cigarettes and marijuana in two to three trials.

Read this if you want to know which school drug prevention programs have the strongest evidence.

Hard drug use reduced in all 7 randomized controlled trials

What the researchers found

Project TND (Towards No Drug Abuse) was evaluated across seven group-randomized controlled trials. In all seven trials, a significant effect was found on hard drug use. The program also showed effects on alcohol use in four trials, and on cigarette and marijuana use in two trials (with a possible third trial showing marijuana effects).

Earlier trials also found effects on violence-related behavior, though this outcome was not assessed in later trials. The consistency of hard drug use effects across seven independent replications is noteworthy for a school-based prevention program.

The authors note that the effects within each trial were statistically significant, with no more than a 10% chance of being obtained by chance alone (two-tailed testing).

Why it matters

Most school-based prevention programs have limited evidence of effectiveness, and few have been replicated in multiple independent trials. The consistent hard drug use reduction across seven trials provides unusually strong evidence that this particular program works.

The numbers in context

7 group-randomized controlled trials. Effects on hard drug use: 7/7 trials. Effects on alcohol: 4/7 trials. Effects on cigarettes: 2/7 trials. Effects on marijuana: 2-3/7 trials.

How the study worked

This is a commentary reviewing the accumulated evidence from seven group-randomized controlled trials of Project TND. The review examines the consistency of effects across replications for different substance use outcomes.

What this study cannot tell us

The commentary format does not provide detailed methodology or effect sizes from each trial. The program effects on marijuana and cigarettes were inconsistent across trials. The author is the program developer, creating potential bias. Violence-related outcomes were not assessed in later trials, so the durability of those effects is unknown.

How to read the evidence

The evidence base of 7 replicated randomized trials is unusually strong for a prevention program, providing robust evidence for hard drug use effects.

When this study was published

Published in 2014. Project TND remains on multiple evidence-based program registries.

The bigger picture

The prevention field is littered with programs that showed promise in one trial but failed to replicate. Project TND's consistent replication across seven trials makes it one of the more robustly supported school-based prevention programs, particularly for hard drug use. The weaker effects on marijuana and cigarettes suggest these behaviors may be harder to prevent through school-based interventions.

Questions still open

Why does Project TND more consistently affect hard drug use than marijuana use? Would the program be effective in different cultural or international contexts? What are the active ingredients that drive the program's success?

Common questions

What is Project Towards No Drug Abuse?

It is a school-based prevention program designed for high school students at risk for substance use. It uses interactive classroom sessions covering motivation, skills, and decision-making to reduce drug use and related behaviors.

Why does it work better for hard drugs than marijuana?

Hard drug use initiation may be more responsive to information and decision-making interventions because the perceived risks are higher. Marijuana use may be more influenced by social norms and peer contexts that are harder to change through classroom programs alone.

Read the original research

Commentary--Project Towards No Drug Abuse: an evidence-based drug abuse prevention program.

The journal of primary prevention, 35(4), 233-7

View on PubMed ↗Publisher’s paper ↗

Citation

Sussman, Steve; Valente, Thomas W; Rohrbach, Louise A; Dent, Clyde W; Sun, Ping. (2014). Commentary--Project Towards No Drug Abuse: an evidence-based drug abuse prevention program.. The journal of primary prevention, 35(4), 233-7. https://doi.org/10.1007/s10935-014-0353-4