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Local Cannabis Policy and Cannabis Use by California High School Students Before and After Statewide Retail
Bethany J Simard1, Alisa A Padon1, Lynn D Silver1
1Public Health Institute, Prevention Policy Group, Berkeley, California.
Purpose:
Although most US states with legalized recreational cannabis retail (RCR) allow some degree of local control, the impact of local policy on cannabis use has seldom been studied. Changes in self-reported cannabis use by California 11th graders pre- and post-RCR legalization (January 2018) were examined, overall and by local policy.
Methods:
Adjusted interrupted time-series multilevel models assessed changes in past 30-day cannabis use post-RCR and tested whether such changes differed by local city and county allowance of storefront and delivery cannabis sales. Cross-sectional data from the 2015/2016 to 2019/2020 California Healthy Kids Surveys were analyzed (n = 377,205).
Results:
Stable pre-RCR odds of any past 30-day cannabis use increased after legalization (odds ratio [OR] [Δ level]: 1.06, p = .013) among all jurisdictions except for those allowing medical delivery only-which decreased-and then slowly declined (OR [Δ slope]: 0.97, p = .001) among all jurisdictions except for those newly allowing storefronts and delivery retail, where elevated rates persisted. Pre-RCR legalization odds of frequent use decreased, whereas post-RCR, they increased through spring 2020 (OR [Δ level]: 1.30, p < .001; OR [Δ slope]: 1.13, p < .001) with no differential changes by local policy. Odds of recent cannabis use and frequent cannabis use were lower in retail-banning jurisdictions without pre-RCR medical sales compared to those allowing storefronts.
Discussion:
Frequent cannabis use among California 11th graders increased post-RCR legalization. After an increase in any 30-day use, use in retail-banning jurisdictions declined, whereas rates in jurisdictions newly permitting storefronts and delivery remained raised. Lower cannabis use in retail-banning jurisdictions pre-RCR suggests pre-existing norms potentially spurred local policies.
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