School Health Program Reduced Marijuana Use by 23% Among High School Students | Research

The takeaway

A multilevel school health program implemented across 237 US high schools was associated with 11% reduced odds of ever using marijuana and 23% reduced odds of current marijuana use among 64,838 students.

School administrators; public health officials; education policy researchers.

23% reduction in current marijuana use (aOR=0.77)

What the researchers found

Students in schools implementing the program had 11% lower odds of ever using marijuana (aOR=0.89, 95% CI 0.81-0.98) and 23% lower odds of current marijuana use (aOR=0.77, 95% CI 0.64-0.93). The program was also associated with reduced sexual risk behaviors and experience of violence.

Why it matters

This is one of the largest evaluations of a school-based program that included cannabis as an outcome. The 23% reduction in current marijuana use demonstrates that comprehensive school health approaches can meaningfully affect adolescent substance use.

The numbers in context

638 schools, 64,838 students. 237 exposed vs 401 unexposed schools. Ever used marijuana: aOR=0.89 (95% CI 0.81-0.98). Current marijuana use: aOR=0.77 (95% CI 0.64-0.93). Also reduced: safety concerns (aOR=0.87), forced sex (aOR=0.76).

How the study worked

Multilevel difference-in-differences analysis comparing 237 exposed schools (30,336 students) to 401 unexposed schools (34,502 students) using 2015 and 2017 Youth Risk Behavior Surveys. The program was a socio-ecological health initiative administered by local education agencies nationwide.

What this study cannot tell us

Quasi-experimental design (schools were selected by local agencies, not randomly assigned). The Youth Risk Behavior Survey is self-reported. Two-year comparison may not capture long-term trends. Schools that implemented the program may have been more motivated for health improvement.

How to read the evidence

Strong: large sample across hundreds of schools with appropriate difference-in-differences methodology, though quasi-experimental.

When this study was published

Published in 2022, using 2015 and 2017 data.

The bigger picture

The program targeted multiple health behaviors simultaneously rather than focusing solely on substance use. The finding that a broad school health approach reduced marijuana use alongside sexual risk behaviors and violence suggests that shared risk factors can be addressed through comprehensive programming.

Questions still open

Which specific program components drove the marijuana reduction? Would the effects persist with longer follow-up? Can the program model be scaled to more schools cost-effectively?

Common questions

What kind of school program reduced marijuana use?

A multilevel, socio-ecological health program that addressed multiple health behaviors simultaneously, including substance use, sexual health, and violence prevention. It was not a "just say no" approach but a comprehensive health initiative.

Does school-based prevention work for marijuana?

This study found a significant 23% reduction in current marijuana use. Combined with similar findings from other school programs (like Climate Schools), the evidence supports comprehensive school health approaches as effective for substance use prevention.

Read the original research

Local Education Agency Impact on School Environments to Reduce Health Risk Behaviors and Experiences Among High School Students.

The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 70(2), 313-321

View on PubMed ↗Publisher’s paper ↗

Citation

Robin, Leah; Timpe, Zachary; Suarez, Nicolas A; Li, Jingjing; Barrios, Lisa; Ethier, Kathleen A. (2022). Local Education Agency Impact on School Environments to Reduce Health Risk Behaviors and Experiences Among High School Students.. The Journal of adolescent health : official publication of the Society for Adolescent Medicine, 70(2), 313-321. https://doi.org/10.1016/j.jadohealth.2021.08.004