What Should We Be Measuring to Know If Cannabis Legalization Is Working?
This scoping review mapped the landscape of recommendations for monitoring the public health impacts of adult-use cannabis legalization—and found significant gaps in what we're actually tracking.
Quick Facts
What This Study Found
As adult-use cannabis legalization expands across the United States, a critical question emerges: how do we know whether it's working as intended? This scoping review searched seven academic databases plus policy research organizations (RAND, Brookings, Pew) to identify what experts recommend monitoring.
The review cataloged recommendations across multiple domains—use prevalence, health outcomes, emergency department visits, traffic safety, youth access, criminal justice impacts, market dynamics, and more. The scope of what experts think should be tracked is vast, reflecting the wide-reaching effects of legalization.
But the gap between what should be monitored and what actually is being monitored is the real finding. Many recommended metrics lack systematic data collection infrastructure. Some outcomes (like long-term health effects) require longitudinal tracking that hasn't been established. And the patchwork of state-level legalization means there's no unified national monitoring system.
The review provides a valuable framework for states that are newly legalizing or for those that want to improve their existing monitoring. It essentially creates a checklist of what the evidence base says we should be watching.
Key Numbers
7 academic databases searched plus 3 policy research centers. Articles coded into standardized monitoring recommendation categories. Recommendations spanned use prevalence, health outcomes, traffic safety, youth access, criminal justice, and market dynamics.
How They Did This
Scoping review searching PubMed/MEDLINE, Embase, Scopus, PsycInfo, Web of Science, Dissertations & Theses Global, and Trip Database from inception to August 2025. Also searched RAND, Brookings, and Pew Research Center websites. Articles coded into key monitoring recommendation areas using a standardized form.
Why This Research Matters
Legalization without monitoring is policy without accountability. If we can't measure the impacts—positive and negative—we can't make evidence-based adjustments. This review provides the roadmap for what comprehensive cannabis legalization monitoring should look like, at a time when most states are doing it piecemeal.
The Bigger Picture
This meta-level review connects to nearly every other study in the database. RTHC-00162's concerns about teen use, RTHC-00143's driving data, RTHC-00161's medical marijuana policy effects, RTHC-00159's workplace testing data—all of these represent individual data points that a comprehensive monitoring system should be systematically collecting. The review essentially provides the framework for turning individual studies into sustained surveillance.
What This Study Doesn't Tell Us
Scoping reviews identify the scope of recommendations but don't evaluate their quality or feasibility. Many recommended metrics may be impractical to collect systematically. The review is U.S.-focused and may not apply to countries with different legalization models. Recommendations exist on paper; whether they translate to actual monitoring programs is a political and funding question.
Questions This Raises
- ?Which monitoring metrics are most feasible to implement at scale?
- ?How should monitoring differ between medical-only and adult-use states?
- ?Would a federal monitoring framework be more effective than state-level systems, or would it lose important local nuance?
Trust & Context
- Key Stat:
- Evidence Grade:
- Scoping review providing a comprehensive map of expert recommendations—useful for framework development but doesn't generate new outcome data.
- Study Age:
- Published in 2025 with searches through August 2025, capturing the most current monitoring recommendations.
- Original Title:
- Adult-use cannabis legalization in the united states: a scoping review of outcome monitoring recommendations.
- Published In:
- BMC public health, 26(1), 87 (2025) — BMC Public Health is a reputable journal focusing on public health research and policy.
- Authors:
- Liu, Yang, Suleiman, Adekemi O, Iverson, Marissa G, Wiser, Alison, Cunningham, Shayna D, O'Grady, Megan A
- Database ID:
- RTHC-06968
Evidence Hierarchy
Maps out the available research on a broad question.
What do these levels mean? →Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-06968APA
Liu, Yang; Suleiman, Adekemi O; Iverson, Marissa G; Wiser, Alison; Cunningham, Shayna D; O'Grady, Megan A. (2025). Adult-use cannabis legalization in the united states: a scoping review of outcome monitoring recommendations.. BMC public health, 26(1), 87. https://doi.org/10.1186/s12889-025-25720-7
MLA
Liu, Yang, et al. "Adult-use cannabis legalization in the united states: a scoping review of outcome monitoring recommendations.." BMC public health, 2025. https://doi.org/10.1186/s12889-025-25720-7
RethinkTHC
RethinkTHC Research Database. "Adult-use cannabis legalization in the united states: a scop..." RTHC-06968. Retrieved from https://rethinkthc.com/research/liu-2025-adultuse-cannabis-legalization-in
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.