(First nation (not jurisdiction) to legalize cannabis use for citizens was Uruguay. This is the tip of the iceberg of issues that liberalization presents)
PMID: 35129240 DOI: 10.1111/add.15840
Background and aim: In Uruguay, residents aged 18 and older seeking legal cannabis must register with the government and choose one of three supply mechanisms: self-cultivation, non-profit cannabis clubs, or pharmacies. This is the first paper to measure the association between type of legal cannabis supply mechanism and traffic crashes involving injuries.
Design: Ecological study using ordinary least squares regression to examine how department-level variation in registrations (overall and by type) is associated with traffic crashes involving injuries.
Cases: 532 department-quarters.
Measurements: Quarterly cannabis registration counts at the department level and incident-level traffic crash data were obtained from government agencies. The analyses controlled for department-level economic and demographic characteristics and, as a robustness check, we included traffic violations involving alcohol for departments reporting this information. Department-level data on crashes, registrations, and alcohol violations were denominated by the number of residents aged 18 and older.
Findings: From 2013-2019, the average number of registrations at the department-quarter level per 10,000 residents aged 18 and older for self-cultivation, club membership, and pharmacy purchasing were 17.7 (standard deviaiton [sd]=16.8), 3.6 (sd=8.6), and 25.1 (sd=50.4), respectively. In our multivariate regression analyses, we did not find a statistically significant association between the total number of registrations and traffic crashes with injuries (β=-0.007; p=0.398; 95% confidence interval [CI]=-.023, .01). Analyses focused on the specific supply mechanisms found a consistent, positive, and statistically significant association between the number of individuals registered as self-cultivators and the number of traffic crashes with injuries (β=0.194; p=0.008; 95% CI=.058, .329). Associations for other supply mechanisms were inconsistent across the various model specifications.
Conclusions: In Uruguay, the number of people allowed to self-cultivate cannabis is positively associated with traffic crashes involving injuries. Individual-level analyses are needed to assess better the factors underlying this association.