Critical review found little evidence that Project TND prevents drug use
A critical reappraisal of seven evaluations of Project TND, a widely used school drug prevention program, found very few main effects on cigarette, alcohol, and marijuana use.
Quick Facts
What This Study Found
This critical review examined all published evaluations of Project Towards No Drug Abuse (Project TND), a school-based prevention program. Across seven evaluation studies, very few main effects were found for cigarette, alcohol, and marijuana use.
While studies reported main effects for "hard drug" use, the reviewer identified numerous threats to validity that may explain these findings, including analytical choices that could inflate results. Similarly, isolated subgroup effects found in early evaluations (such as effects on alcohol use among baseline nonusers) were not replicated in later studies, suggesting they may have resulted from multiple comparisons.
The reviewer concluded there was little evidence to support the assertion that Project TND is an effective drug or violence prevention program.
Key Numbers
Seven evaluations reviewed. Very few main effects found for cigarettes, alcohol, or marijuana. Reported hard drug effects had "numerous threats to validity." Early subgroup effects were not replicated in later studies.
How They Did This
Critical review of publications from all seven evaluation studies of Project TND, examining main effects on drug use, subgroup analyses, and violence-related outcomes with attention to methodological rigor and replication.
Why This Research Matters
Project TND was classified as evidence-based by several registries and widely disseminated. This critical review raised important questions about the evidence threshold used to label prevention programs as effective and the consequences of widespread implementation of programs with limited evidence.
The Bigger Picture
The broader implication is about how prevention science evaluates its own evidence. When early positive findings are not replicated and may result from analytical choices, the "evidence-based" label can be misleading. The review called for higher standards of evidence before programs are widely disseminated.
What This Study Doesn't Tell Us
This is one reviewer's critical assessment and may be subject to its own interpretive biases. Not all researchers may agree with the severity of the methodological concerns raised. The review did not conduct a new analysis of the original data.
Questions This Raises
- ?Should evidence-based prevention registries revise their criteria?
- ?Are other widely disseminated prevention programs similarly lacking in rigorous evidence?
- ?What level of evidence should be required before a prevention program is implemented in schools?
Trust & Context
- Key Stat:
- Very few main effects on marijuana, alcohol, or cigarette use across seven evaluations
- Evidence Grade:
- Critical review of existing evaluations, raising methodological concerns about a program classified as evidence-based.
- Study Age:
- Published in 2014.
- Original Title:
- Is Project Towards No Drug Abuse (Project TND) an evidence-based drug and violence prevention program? A review and reappraisal of the evaluation studies.
- Published In:
- The journal of primary prevention, 35(4), 217-32 (2014)
- Authors:
- Gorman, Dennis M
- Database ID:
- RTHC-00800
Evidence Hierarchy
Summarizes existing research on a topic.
What do these levels mean? →Frequently Asked Questions
Does Project TND prevent marijuana use?
This critical review found very few main effects on marijuana use across seven evaluations of the program. Effects reported for "hard drugs" had significant methodological concerns.
Why does this matter?
Project TND was widely disseminated as an "evidence-based" program. If the evidence supporting it is weaker than reported, schools may be investing resources in a program that does not meaningfully prevent substance use.
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Cite This Study
https://rethinkthc.com/research/RTHC-00800APA
Gorman, Dennis M. (2014). Is Project Towards No Drug Abuse (Project TND) an evidence-based drug and violence prevention program? A review and reappraisal of the evaluation studies.. The journal of primary prevention, 35(4), 217-32. https://doi.org/10.1007/s10935-014-0348-1
MLA
Gorman, Dennis M. "Is Project Towards No Drug Abuse (Project TND) an evidence-based drug and violence prevention program? A review and reappraisal of the evaluation studies.." The journal of primary prevention, 2014. https://doi.org/10.1007/s10935-014-0348-1
RethinkTHC
RethinkTHC Research Database. "Is Project Towards No Drug Abuse (Project TND) an evidence-b..." RTHC-00800. Retrieved from https://rethinkthc.com/research/gorman-2014-is-project-towards-no
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.