Marijuana Use Linked to Lower College Completion Rates, Especially at Four-Year Schools
In a nationally representative study of matched college students, past-year marijuana use was associated with 30% lower college completion at four-year schools, while methamphetamine and alcohol treatment predicted lower completion at two-year schools.
Quick Facts
What This Study Found
Among propensity-matched four-year college students, past-year marijuana use was associated with lower completion (IRR = 1.30, p = 0.007), with stronger effects for frequent use (>=5 times/month, IRR = 1.44). Two-year students showed different patterns: methamphetamine and alcohol treatment, not marijuana, predicted lower completion.
Key Numbers
888 two-year and 1,398 four-year matched students; past-year marijuana IRR 1.30; >=5 times/month IRR 1.44; 7-year follow-up; matched on 15 variables.
How They Did This
Propensity-matched analysis from Add Health. 888 two-year and 1,398 four-year college students matched on 15 measures. Educational attainment measured 7 years later.
Why This Research Matters
This study separates effects of different substances on educational attainment at different institution types, finding marijuana specifically affects four-year completion but not two-year.
The Bigger Picture
As marijuana legalization expands, the dose-response pattern and different patterns at two-year versus four-year schools suggest tailored intervention approaches may be needed.
What This Study Doesn't Tell Us
Observational design cannot prove marijuana caused lower completion. Propensity matching reduces but does not eliminate confounding.
Questions This Raises
- ?Why does marijuana appear to affect four-year but not two-year college completion?
- ?Would targeted academic functioning interventions improve completion rates?
Trust & Context
- Key Stat:
- 30% lower college completion with past-year marijuana use at four-year schools
- Evidence Grade:
- Large nationally representative cohort with propensity matching and 7-year follow-up, limited by observational design.
- Study Age:
- 2024 publication using Add Health data
- Original Title:
- Substance Use and College Completion Among Two-Year and Four-Year College Students From a Nationally Representative Longitudinal Study.
- Published In:
- Cureus, 16(5), e61297 (2024)
- Authors:
- Rosenbaum, Janet E
- Database ID:
- RTHC-05663
Evidence Hierarchy
Frequently Asked Questions
Does marijuana affect college graduation rates?
Past-year marijuana use was associated with 30% lower completion at four-year colleges, increasing to 44% for students using 5+ times per month. Marijuana did not significantly predict completion at two-year colleges.
Is the effect of marijuana on college different from alcohol?
Yes. At four-year schools, marijuana predicted lower completion while alcohol did not. At two-year schools, alcohol treatment history predicted lower completion but marijuana did not.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-05663APA
Rosenbaum, Janet E. (2024). Substance Use and College Completion Among Two-Year and Four-Year College Students From a Nationally Representative Longitudinal Study.. Cureus, 16(5), e61297. https://doi.org/10.7759/cureus.61297
MLA
Rosenbaum, Janet E. "Substance Use and College Completion Among Two-Year and Four-Year College Students From a Nationally Representative Longitudinal Study.." Cureus, 2024. https://doi.org/10.7759/cureus.61297
RethinkTHC
RethinkTHC Research Database. "Substance Use and College Completion Among Two-Year and Four..." RTHC-05663. Retrieved from https://rethinkthc.com/research/rosenbaum-2024-substance-use-and-college
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.