Recreational Marijuana Availability in Oregon and Use Among Adolescents

Young Adults' Experiences with Cannabis Retailer Marketing and Related Practices: Differences Among Sociodemographic Groups and Associations with Cannabis Use-related Outcomes

OBJECTIVES

Limited cannabis retail surveillance has been conducted, particularly assessing retailer practices in relation to consumer sociodemographic factors or use-related outcomes. This study examined young adults': exposure to promotions, health claims, warnings, and age restrictions at cannabis retailers; demographic correlates of retail exposures; and retail exposures in relation to use-related outcomes.

STUDY DESIGN

This study used the cross-sectional quantitative analysis.

METHODS

We analyzed 2023 survey data among 876 young adults in states with legal non-medical cannabis, reporting past-month cannabis use and past-year retailer visits.

RESULTS

In this sample (Mage = 27.1, 44.1% male, 31.7% sexual minority, 17.7% Black, 11.2% Asian, 25.1% Hispanic), 46.7% "at least sometimes" noticed free samples, 76.5% price promotions, 37.4% subpopulation-targeted promotions; 72.5% health claims on products/ads, 63.1% signage, and 70.5% from budtenders; 72.5% warnings on labels, 65.5% signage, and 38.9% from budtenders; and > 80% age verifications. Multivariable analyses identified sociodemographic correlates of exposure outcomes: greater promotion exposure was associated with Black race; greater health claim exposure with being heterosexual, Black, and less educated; less warning exposure with less education; and less age restriction exposure with being younger, male, and Black. Retail exposures were associated with use-related outcomes: more frequent cannabis use was associated with less health claim exposure; greater perceived social acceptability with greater promotion and age restriction exposure; greater perceived risk with greater warning and less age restriction exposure; more problematic use and driving after use with greater promotion and less age restriction exposure.

CONCLUSIONS

Cannabis retail exposure disparities and their associations with use-related outcomes highlight the importance of regulatory and prevention efforts.

Understanding youth and young adult cannabis use in Canada post-legalization: a scoping review on a public health issue

BACKGROUND

Canada legalized recreational cannabis in 2018, and one of the primary objectives of the Cannabis Act was to protect youth by reducing their access to cannabis and providing public education. Canada has the highest prevalence of cannabis use worldwide, particularly among youth and young adults under the age of 25. Cannabis use is linked with many adverse effects for youth and young adults including psychosis, anxiety, depression, respiratory distress, cannabinoid hyperemesis syndrome, and impaired cognitive performance. Despite the high prevalence of cannabis use and the evolution of policies in Canada and globally, significant knowledge and research gaps remain regarding youth and young adult cannabis use. The aim of this scoping review is to map the extent, nature, and range of evidence available on youth and young adult cannabis use in Canada since its legalization, in order to strengthen policies, services, treatments, training, and public education strategies.

METHODS

Using a scoping review framework developed by Arksey and O'Malley, along with the PRISMA-ScR guidelines, we conducted a rigorous search in five academic databases: MEDLINE, Embase, APA PsycINFO, CINAHL and Web of Science Core Collection. We included empirical studies that collected data in Canada after the legalization of recreational cannabis (October 2018) and focused on youth or young adults < 30. Two reviewers independently screened articles in two stages and extracted relevant information from articles meeting the inclusion criteria.

RESULTS

Of the 47 articles meeting our inclusion criteria, 92% used quantitative methods, 6% were qualitative, and 2% used a mixed-methods approach. Over two-thirds (68%) used secondary data. These studies were categorized into six focus areas: (1) prevalence, patterns, and trends, (2) cannabis-related injuries and emergency department (ED) visits, (3) rates and patterns during the pandemic, (4) perceptions of cannabis use, (5) prevention tools, and (6) cannabis-related offenses. Key findings from the studies reviewed include an increase in cannabis use among 18-24-year-olds post-legalization, with mixed results for youth under 18. ED visits for intentional and unintentional cannabis-related injuries have increased in young children and teens. Perception studies show a mix of concern and normalization of cannabis use. Though limited, prevention studies are promising in raising awareness. A decline in cannabis-related offenses was noted by one study. The review highlights several research gaps, including the need for more qualitative data, disaggregation of demographic data, intervention research, and comprehensive studies on the physical and mental health impacts of cannabis use among youth and young adults.

CONCLUSION

Maintaining a public health approach is critical, with a focus on reducing the high prevalence of cannabis use among youth and young adults. This involves implementing prevention strategies to minimize harms, enhancing public education, minimizing commercialization, reducing youth access to cannabis, promoting guidelines for lower-risk cannabis use and harm reduction strategies, and increasing training for healthcare providers.

Increasing lifetime and past 30-day marijuana use among middle school students regardless of recreational marijuana sales

PURPOSE

This study investigated whether adult use marijuana sales were associated with changes in lifetime and past 30-day (P30D) marijuana use among middle school students in Nevada (NV), which had adult-use marijuana sales during the study period, compared to New Mexico (NM), which did not have adult-use marijuana sales during the study period.

METHODS

Data were drawn from the middle school 2017 and 2019 NV Youth Risk Behavior and NM Youth Risk and Resiliency Surveys. Difference-in-difference analyses compare changes in lifetime and P30D marijuana use in NV (adult-use sales implemented July 2017) vs. NM (no adult-use sales during the study period).

RESULTS

There was no difference in lifetime (aOR 1.11; 95% CI 0.91,1.36) and P30D (aOR 1.17; 95% CI 0.91,1.51) marijuana use by adult-use sales status. The odds of lifetime and P30D marijuana use increased in both states, particularly among students who were female, older, non-White, or attending a Title 1 school.

DISCUSSION

Adult-use sales were not associated with an increase in lifetime or P30D marijuana use. State-level prevention efforts should focus on sub-populations with increasing lifetime and P30D use regardless of adult-use sales status.

National and regional trends in seizures of shrooms (psilocybin) in the United States, 2017-2022

BACKGROUND

Psilocybin, the principle psychoactive component in "shrooms", is regaining acceptance in therapeutic settings, leading to media coverage of medical benefits associated with use. Possession is also becoming increasingly decriminalized throughout the United States. There is a lack of data on prevalence of shroom use, but trends in law enforcement seizure data can provide one indicator of shroom availability in US communities. We determined whether seizures of shrooms have shifted between 2017 and 2022.

METHODS

This study examined national and regional trends in counts and total weight of shroom seizures reported to High Intensity Drug Trafficking Areas in the US between 2017 and 2022 (N=4526).

RESULTS

There were 402 seizures in 2017 compared to 1396 in 2022 with the plurality occurring in the Midwest (36.0%), followed by the West (33.5%). Between 2017 Quarter 1 (Q1) and 2022 Quarter 4 (Q4), the number of seizures increased by 368.9% (AQPC=7.0; 95 CI: 5.9-8.1) and there were significant increases in all four regions. In terms of weight, 226.0kg was seized in 2017 vs. 844.0kg in 2022, and the greatest total weight in seizures was in the West (1864.2kg, 42.6%), followed by the South (1831.9kg, 41.8%). Between 2017 Q1 and 2022 Q4, the total weight seized in the US increased by 2749.7% (AQPC=6.2, 95% CI: 0.3-12.4) and there were significant increases in all four regions.

CONCLUSIONS

Seizures of shrooms have increased, suggesting that availability may be escalating; thus, increases in prevention efforts and harm reduction education are warranted.

Is legalization of recreational cannabis associated with levels of use and cannabis use disorder among youth in the United States? A rapid systematic review

Cannabis legalization policies are rapidly changing in the United States. While there are concerns that recreational legalization will negatively affect young people, previous reviews have not provided clear indication of such effects. The purpose of this rapid systematic review was to examine whether recreational legalization was associated with increases in prevalence of cannabis use and use disorder among adolescents and young adults. PubMed/MEDLINE, Embase, Scopus, PsycInfo, Web of Science, Dissertations & Theses Global, the Trip Database, and OpenGrey were searched from date of inception through Marcy 17, 2022 to retrieve all relevant records. English language and human subject filters were applied. Two reviewers screened abstracts and titles, assessed full text articles, and coded the final included articles. Studies including primarily 10- to 19-year-olds were classified as adolescent, and those between 18 and 26 years as young adult. Our search identified 33 research reports (22 with adolescent samples; 14 young adult). For adolescents, ten studies reported no change in use prevalence associated with legalization, six reported a decrease, and seven reported an increase. Among young adults, most studies (8) showed an increase in at least one prevalence measure, four showed no change, and one showed a decrease. Only two adolescent and one young adult study examined cannabis use disorder, both adolescent studies showed an increase, and the young adult showed no change. The majority of studies had risk of bias. Recreational legalization may be associated with increases in prevalence of cannabis use in young adults while results for adolescents are mixed. Policymakers and practitioners should consider appropriate prevention and treatment options for young people.Trial Registration: PROSPERO #CRD42021276984.

Youth Exposure to Recreational Cannabis Legalization: Moderation of Effects by Sex and Parental Cannabis Use during Adolescence

OBJECTIVE

Few studies of recreational cannabis legalization (RCL) have assessed adolescents both before and after RCL or considered moderators of RCL effects. The present study tested whether RCL was more strongly associated with cannabis use for girls and among youth whose parents had a history of cannabis use during adolescence.

METHOD

Data were pooled from 940 adolescents from three intergenerational studies that began in Washington (where RCL was enacted in 2012), Oregon (RCL year = 2015), and New York (RCL year = 2021). Youth were assessed repeatedly from ages 13 to 18 years (k = 3,650 person-years) from 1999 to 2020 (prior to RCL in New York). Parent cannabis use at or before age 18 years (yes/no) was assessed prospectively during the parent's adolescence. Multilevel models focused on the between-subjects effects of years of youth exposure to RCL on adolescents' mean cannabis use likelihood, and interactions with child sex and parent use history.

RESULTS

Child exposure to RCL was associated with a higher likelihood of cannabis use if their parents had a history of adolescent use, (Estimate [SE] = 0.67 [0.25], p = 0.008), versus no such history (Estimate [SE] = -0.05 [0.28], p = 0.855). RCL effects were not moderated by child sex.

CONCLUSIONS

The effects of RCL on adolescents' cannabis use may depend on their parents' history of using the drug. Identifying other moderators of RCL effects, and understanding the mechanisms of these risks and the ways that parents and communities can offset them, are prevention priorities.

Young Adult Depression and Cannabis Use: Associations Before and After Recreational Legalization

INTRODUCTION

The co-occurrence of depression with cannabis use worsens both mood and substance use disorder outcomes, with young adults particularly at risk of co-occurrence. This research investigates whether the association of state-level prevalence rates of young adult (age 18-25) depression and cannabis use in the U.S. changed following enactment of recreational (adult use) cannabis legalization between 2008 and 2019.

METHODS

Annual, state prevalence data on past-year major depressive episode (hereafter, depression) and past-month cannabis use were extracted from the National Survey on Drug Use and Health (N=600 state-year observations). Moderated regression models tested whether the association of depression with cannabis use differed before versus after recreational legalization by comparing prevalence rates of depression and cannabis use in states that enacted recreational legalization to those that did not, while fixing state, year, and medical legalization effects. Data were accessed and analyzed in 2023.

RESULTS

Prevalence rates of both depression and cannabis use increased throughout the study period. The positive statistical effect of depression on cannabis use more than doubled in magnitude after legalization (β=0.564, 95% CI=0.291, 0.838) as compared to before (β=0.229, 95% CI=0.049, 0.409), representing a significant change (β=0.335, 95% CI=0.093, 0.577).

CONCLUSIONS

These results suggest that the association between prevalence rates of young adult depression and cannabis use strengthened following recreational legalization in the U.S. This is potentially due to increases in cannabis accessibility and the acceptance of the health benefits of cannabis, which may enhance the use of cannabis as a coping mechanism among young adults with depression.

Legalization and retail availability of recreational marijuana and adolescent use in schools

Legalization of use and retail sales of recreational marijuana in U.S. states and the associated potential increase in access to marijuana and normalization of its use by adults could lead to increased use by adolescents. Studies have found that states with legal recreational marijuana have higher rates of adolescent use and frequency of use compared to states without legal use. We examined changes in student office discipline referrals (ODRs) for substance use offenses in Oregon middle and high schools before and after the legalization of recreational marijuana relative to comparison schools in other states. We found that rates of substance use related ODRs in middle schools increased by 0.14 per 100 students (30% of the mean) with legalization relative to comparison schools. This increase was moderated by the presence of a marijuana outlet within one mile of the school. We found no statistically discernible changes in high school ODRs. Marijuana use in adolescence has been linked to negative health and social consequences, including academic problems, mental health issues, and impaired driving. Potential adverse impact on adolescents and investments in school-based prevention programs could be important considerations for policymakers and public health officials when evaluating marijuana legalization.

Health, safety, and socioeconomic impacts of cannabis liberalization laws: An evidence and gap map

Background

Globally, cannabis laws and regulations are rapidly changing. Countries are increasingly permitting access to cannabis under various decriminalization, medicalization, and legalization laws. With strong economic, public health, and social justice incentives driving these domestic cannabis policy reforms, liberalization trends are bound to continue. However, despite a large and growing body of interdisciplinary research addressing the policy-relevant health, safety, and socioeconomic consequences of cannabis liberalization, there is a lack of robust primary and systematic research that comprehensively investigates the consequences of these reforms.

Objectives

This evidence and gap map (EGM) summarizes the empirical evidence on cannabis liberalization policies. Primary objectives were to develop a conceptual framework linking cannabis liberalization policies to relevant outcomes, descriptively summarize the empirical evidence, and identify areas of evidence concentration and gaps.

Search Methods

We comprehensively searched for eligible English-language empirical studies published across 23 academic databases and 11 gray literature sources through August 2020. Additions to the pool of potentially eligible studies from supplemental sources were made through November 2020.

Selection Criteria

The conceptual framework for this EGM draws upon a legal epidemiological perspective highlighting the causal effects of law and policy on population-level outcomes. Eligible interventions include policies that create or expand access to a legal or decriminalized supply of cannabis: comprehensive medical cannabis laws (MCLs), limited medical cannabidiol laws (CBDLs), recreational cannabis laws (RCLs), industrial hemp laws (IHLs), and decriminalization of cultivations laws (DCLs). Eligible outcomes include intermediate responses (i.e., attitudes/behaviors and markets/environments) and longer-term consequences (health, safety, and socioeconomic outcomes) of these laws.

Data Collection and Analysis

Both dual screening and dual data extraction were performed with third person deconfliction. Primary studies were appraised using the Maryland Scientific Methods Scale and systematic reviews were assessed using AMSTAR 2.

Main Results

The EGM includes 447 studies, comprising 438 primary studies and nine systematic reviews. Most research derives from the United States, with little research from other countries. By far, most cannabis liberalization research focuses on the effects of MCLs and RCLs. Studies targeting other laws-including CBDLs, IHLs, and DCLs-are relatively rare. Of the 113 distinct outcomes we documented, cannabis use was the single most frequently investigated. More than half these outcomes were addressed by three or fewer studies, highlighting substantial evidence gaps in the literature. The systematic evidence base is relatively small, comprising just seven completed reviews on cannabis use (3), opioid-related harms (3), and alcohol-related outcomes (1). Moreover, we have limited confidence in the reviews, as five were appraised as minimal quality and two as low quality.

Authors’ Conclusions

More primary and systematic research is needed to better understand the effects of cannabis liberalization laws on longer-term-and arguably more salient-health, safety, and socioeconomic outcomes. Since most research concerns MCLs and RCLs, there is a critical need for research on the societal impacts of industrial hemp production, medical CBD products, and decriminalized cannabis cultivation. Future research should also prioritize understanding the heterogeneous effects of these laws given differences in specific provisions and implementation across jurisdictions.

Proximity to Legal Cannabis Stores in Canada and Use of Cannabis Sources in the First Three Years of Legalization, 2019-2021

OBJECTIVE

The accessibility of legal cannabis in Canada may influence how consumers source their cannabis. The aims of this study were to examine (a) the distance between respondents' homes and legal retail stores, (b) the cannabis sources used in the past 12 months, and (c) the association between cannabis sources used and distance to legal retail stores.

METHOD

Data were analyzed from Canadian respondents participating in the International Cannabis Policy Study from 2019 to 2021. Respondents were 15,311 past-12-month cannabis consumers of legal age to purchase cannabis. Weighted logistic regression models examined cannabis sources used and their association with the Euclidean distance to the nearest legal store, province of residence, and year (n = 12,928).

RESULTS

Respondents lived closer to a legal retail store in 2021 (1.5 km) versus 2019 (6.8 km) as the number of retail stores increased. Respondents in 2020 and 2021 had higher odds of obtaining cannabis from legal sources (e.g., legal stores: 47.9% and 60.0% vs. 38.6%, respectively, adjusted odds ratio [AOR] range: 1.41-2.42) and lower odds of obtaining cannabis from illegal sources versus 2019 (e.g., dealers: 22.6% and 19.9% vs. 29.1%, respectively, AOR range: 0.65-0.54). Respondents who lived closest to legal stores had higher odds of sourcing from legal stores and lower odds of sourcing from legal websites or growing their own cannabis.

CONCLUSIONS

Legal cannabis stores are increasingly accessible to people living in Canada 3 years after legalization. Household proximity to a legal cannabis store was associated with sourcing cannabis from legal retail stores, but only among those who live very close (<3 km). Findings suggest that proximity to legal cannabis stores may aid uptake of the legal market, yet there may be diminishing returns after a certain point.

Adolescent Advertising Exposure to Cannabis Products in Rural Oklahoma via Medical Dispensaries

OBJECTIVE

We assess cannabis advertising exposure among adolescents in rural Oklahoma from medical dispensaries.

METHOD

Our mixed-methods study identified medical dispensaries within a 15-minute drive time of rural Oklahoma high schools. Study staff completed observational data collection forms and took photographs of each dispensary. Quantitative data from the forms and qualitative coding of photographs were used to describe dispensary characteristics and likely advertising exposure for adolescents.

RESULTS

Ninety-two dispensaries were identified across 20 rural communities. The majority presented as retail spaces (n = 71). Product (n = 22) and price promotions (n = 27) were common. Coding of dispensary photographs found that product promotions advertised cannabis use modalities, with cannabis flower being the most common (n = 15), followed by edibles (n = 9) and concentrates (n = 9). Among dispensaries with price promotions, discounts (n = 19) and prices under $10 (n = 14) were common.

CONCLUSIONS

Sampled rural medical dispensaries present as retail spaces and are a likely source of adolescent cannabis advertising exposure.

Recreational Marijuana Legalization, Local Retail Availability, and Alcohol and Marijuana Use and Co-Use Among California High School Students

OBJECTIVE

This study examined whether recreational marijuana legalization (RML) and local retail availability were associated with marijuana and alcohol use and co-use among adolescents.

METHOD

We investigated associations between RML and past-30-day marijuana and alcohol use and co-use, and moderating effects of retail availability of marijuana and alcohol, using data from the 2010-2011 to 2018-2019 California Healthy Kids Surveys (CHKS) of 9th and 11th grade students in 38 California cities. Multilevel mixed-effects logistic regression analyses were conducted, controlling for secular trends and student and city demographics. Additional analyses examined associations of RML and retail availability with co-use among subgroups of drinkers and marijuana users.

RESULTS

For the full sample, RML was inversely associated with alcohol use but was not significantly associated with marijuana use or co-use with alcohol. However, significant interactions between RML and marijuana outlet density showed that there were increases in marijuana and alcohol co-use and alcohol following legalization in cities with higher densities of marijuana outlets. RML was positively associated with co-use among non-heavy and heavy drinkers, but inversely related to co-use among occasional and frequent marijuana users. A significant positive interaction between RML and marijuana outlet density indicated that RML was associated with increases in co-use for occasional marijuana users in cities with higher densities of marijuana outlets.

CONCLUSIONS

RML was associated with increases in marijuana and alcohol co-use and alcohol use among California high school students, particularly those in cities with higher densities of retail cannabis stores, although this varied across alcohol and marijuana use subgroups.

Recreational Cannabis Legalization and Proximity to Cannabis Retailers as Risk Factors for Adolescents' Cannabis Use

Within-person studies are lacking regarding how recreational cannabis legalization (RCL) and the numbers of neighborhood cannabis retailers relate to adolescents' cannabis use. Study participants were 146 offspring (55% girls; 77% White non-Latinx) of men recruited in childhood from neighborhoods with high delinquency rates. Youth were assessed for past-year cannabis and alcohol use one or more times from ages 13 to 20 years (age M[SD] = 16.4 [2.1] years across 422 observations), while they were living in Oregon or Washington from 2005 to 2019 (where cannabis retail stores opened to adults ages 21 years and older in 2014 and 2015, respectively). We calculated distances between addresses of licensed cannabis retailers and participants' homes. Multilevel models that accounted for effects of age on cannabis use did not support that the number of retail stores within 2-, 5-, 10-, or 20-mile radii of adolescents' homes increased likelihood of past-year cannabis use at the within- or between-subjects levels. Likewise, primary models did not support a greater likelihood of cannabis use among youth whose adolescence coincided more fully with the post-RCL period. A secondary model suggested that after adjusting for adolescents' concurrent alcohol use as a marker of general substance use risk, RCL was associated with cannabis use (between-subjects B [95% CI] = .35 [.05-.66], p = .024). Further research is needed with larger prospective samples, at-risk subgroups, and as cannabis markets mature.

Normalization of Prevention Principles and Practices to Reduce Substance Use Disorders Through an Integrated Dissemination and Implementation Framework

Major research breakthroughs over the past 30 years in the field of substance use prevention have served to: (1) enhance understanding of pharmacological effects on the central and peripheral nervous systems and the health and social consequences of use of psychoactive substances, particularly for children and adolescents; (2) delineate the processes that increase vulnerability to or protect from initiation of substance use and progression to substance use disorders (SUDs) and, based on this understanding, (3) develop effective strategies and practices to prevent the initiation and escalation of substance use. The challenge we now face as a field is to "normalize" what we have learned from this research so that it is incorporated into the work of those involved in supporting, planning, and delivering prevention programming to populations around the world, is integrated into health and social service systems, and helps to shape public policies. But we wish to go further, to incorporate these effective prevention practices into everyday life and the mind-sets of the public, particularly parents and educators. This paper reviews the advances that have been made in the field of prevention and presents a framework and recommendations to achieve these objectives generated during several meetings of prevention and implementation science researchers sponsored by the International Consortium of Universities for Drug Demand Reduction (ICUDDR) that guides a roadmap to achieve "normalization."

Cannabis retailer marketing strategies and regulatory compliance: A surveillance study of retailers in 5 US cities

As cannabis retail expands in the US, its surveillance is crucial to inform regulations and protect consumers. This study addresses this need by conducting point-of-sale audits examining regulatory compliance (e.g., age verification, signage), advertising/promotional strategies, products, and pricing among 150 randomly-selected cannabis retailers in 5 US cities (30/city: Denver, Colorado; Seattle, Washington; Portland, Oregon; Las Vegas, Nevada; Los Angeles, California) in Summer 2022. Descriptive and bivariate analyses characterized the retailers overall and across cities. Age verification rates were high (>90%). The majority of retailers had signage indicating restricted access (e.g., no minors; 87.3%), onsite consumption (73.3%), and distribution to minors (53.3%). Retailers were likely to post warnings regarding use during pregnancy/breastfeeding (72.0%), followed by health risks (38.0%), impacts on children/youth (18.7%), and DUI (14.0%). Overall, 28.7% posted health claims, 20.7% posted youth-oriented signage, and 18.0% had youth-oriented packaging. Price promotions were prevalent, particularly price specials (75.3%), daily/weekly/monthly specials (66.7%), and membership programs (39.3%). One-fourth had signs/promotions indicating curbside delivery/pick-up (28.0%) and/or online ordering (25.3%); 64.7% promoted their website or social media page. The most potent cannabis products were most often e-liquids (38.0%) or oils (24.7%); the least potent were often edibles (53.0%). The most expensive product was often bud/flower (58.0%); the least was joints (54.0%). The vast majority (≥81%) sold vaporizers, wrapping papers, and hookah/waterpipes/bongs, and 22.6% sold CBD products. Marketing strategies differed across cities, reflecting differences in state-specific regulations and/or gaps in compliance/enforcement. Findings underscore the need for ongoing cannabis retail surveillance to inform future regulatory and enforcement efforts.

Associations of recreational cannabis dispensaries' availability, storefront signage and health benefit signs with cannabis use: findings from a representative adult sample in California, United States

BACKGROUND AND AIMS

There are concerns that availability of recreational cannabis dispensaries (RCDs) and point-of-sale marketing may lead to increased cannabis use in jurisdictions where cannabis retail sale is legal. This paper examined whether the availability RCDs and the presence of storefront signage indicative of cannabis and signs promoting health benefits in RCDs were associated with cannabis use and risk perceptions.

DESIGN

Cross-sectional, secondary data analysis.

SETTING

California, USA.

PARTICIPANTS

A representative sample of 3385 adults in California who participated in the 2020 probability-based Marijuana Use and Environment Survey.

MEASUREMENTS

Binary outcomes included past-month overall cannabis use, perceiving cannabis smoking as harmful and past-month cannabis use by purpose (medical only, recreational only and dual). The objectively assessed predictors included proximity and density of RCDs and presence of storefront signage indicative of cannabis and signs promoting health benefits in RCDs.

FINDINGS

In terms of proximity, thepresence of storefront signage in the nearest RCD was associated with smaller odds of perceiving cannabis smoking as harmful [odds ratio (OR) = 0.63, 95% confidence interval (CI) = 0.39, 0.99] if the RCD was located within 2 miles of home. Presence of health benefit signs in the nearest RCD was associated with greater odds of overall cannabis use (OR = 2.45, 95% CI = 1.17, 5.16) and recreational use (OR = 3.50, 95% CI = 1.027, 11.91) if the RCD was located within 2-4 miles of home. In terms of density, count of RCDs, count of RCDs with storefront signage and count of RCDs with health benefit signs within 2 miles of home were each separately associated with greater odds of overall cannabis use and cannabis use for dual purposes.

CONCLUSIONS

The availability of recreational cannabis dispensaries within 2 miles of one's home and the presence of storefront signage indicating the availability of cannabis and signs promoting health benefits of cannabis appear to be associated with increased cannabis use and reduced risk perceptions among adults in California, USA.

Minimum legal age laws and perceived access to cigarettes, e-cigarettes, and other substances among youth in Canada, England, and the United States: 2017-2021

BACKGROUND

Minimum legal age (MLA) restrictions are a core policy to reduce youth use of tobacco, e-cigarettes, and other substances. We examined trends in perceived ease of access to tobacco and other substances across three countries with differing MLA policies, including the United States (US), which increased the federal MLA for tobacco products from 18 to 21 in 2019.

METHODS

Repeat cross-sectional data were analyzed from seven waves of the International Tobacco Control (ITC) Youth Tobacco and Vaping Survey conducted between 2017 and 2021. Online surveys were conducted with non-probability samples of 91,647 youth aged 16-19 in Canada, England, and the US. Regression models were used to examine differences in perceived ease of accessing each of 7 substances (analyzed as "very easy" or "fairly easy" versus else), and differences between countries and over time (including before and after any MLA changes) for cigarettes, e-cigarettes, cannabis, and alcohol; additional models examined sub-national variation in MLA.

RESULTS

Perceived access varied by substance and across countries: in August/September 2021, perceived ease of accessing cigarettes and e-cigarettes was greater in Canada where MLA was 18-19 (61.7% cigarettes, 66.4% e-cigarettes) and England where MLA was 18 (66.9%, 69.6%), compared to the US where MLA was 21 (48.0%, 60.9%; p < 0.001 for all). Perceived ease of accessing cannabis was greatest in Canada (53.3%), followed by the US (44.1%) and England (34.0%; p < 0.001 for all). Following the federal MLA increase for tobacco products in the US, perceived ease of access decreased significantly for cigarettes (65.1% in 2019Aug to 59.7% in 2020Feb; aOR=0.80 (95%CI=0.71-0.89)) and e-cigarettes (72.4% in 2019Aug to 69.4% in 2020Feb; aOR=0.87 (95%CI=0.77-0.98)).

CONCLUSIONS

Higher MLA was strongly associated with fewer youth perceiving easy access to substances: perceived access varied between countries with differing MLA, as well as within-country before and after changes to MLA.

The impact of legal cannabis availability on cannabis use and health outcomes: A systematic review

BACKGROUND

For alcohol, regulating availability is an effective way to reduce consumption and harm. Similarly, the higher availability of medical cannabis dispensaries has been linked to increased cannabis consumption and harm. For recreational cannabis markets, such a link is suspected but still poorly understood.

METHODS

A systematic literature review (PROSPERO registration number 342357) was conducted on 1 July 2022 in common libraries (Medline, Web of Science, PsycInfo, Psyndex, CINAHL, Embase, SCOPUS, Cochrane) for publications since 2012. Studies linking variations in the availability of legal cannabis products to behavioral outcomes (cannabis use or related health indicators) were included, while studies focusing solely on the legalization of medical cannabis were excluded. The risk of bias was assessed using an adapted version of the Newcastle-Ottawa-Scale.

RESULTS

After screening n = 6,253 studies, n = 136 were selected for full-text review, out of which n = 13 met the inclusion criteria, reporting on n = 333,550 study participants and n = 855,630 presentations to emergency departments. All studies were conducted in North America, with the majority from Western US states. Using longitudinal (n = 1), cross-sectional (n = 4), or repeated cross-sectional (n = 8) study designs, an increased availability of legal cannabis was linked to increased current cannabis use and health-related outcomes (vomiting, psychosis, or cannabis-involved pregnancies), regardless of the indicator employed to measure availability (proximity or density) among both adults and adolescents. The positive correlation between cannabis availability and consumption is most pronounced among those groups who have been less exposed to cannabis before legalization. The association between the availability of legal cannabis and risky use indicators was less consistent.

CONCLUSIONS

Groups who have been least exposed to cannabis before legalization may be most susceptible to increased availability. In jurisdictions with legal cannabis markets, restrictions on the number of legal cannabis retailers, especially in densely populated areas, appear warranted.

Assessing the Impact of Recreational Cannabis Legalization on Cannabis Use Disorder and Admissions to Treatment in the United States

Purpose of Review

Policy implications from changes in recreational cannabis laws (RCLs) have raised public health concerns. While numerous studies have examined the impact of RCLs on cannabis use, there is less research on the risk of developing cannabis use disorder (CUD). This review summarizes the latest research on the effects of RCLs on CUD prevalence and cannabis treatment admissions.

Recent Findings

Nine studies were published between 2016 - 2022 that examined RCLs and CUD or treatment. Findings generally indicate an increase in CUD prevalence associated with legalization, but effects differ by age group. There was no significant association between legalization and CUD treatment admissions, and CUD admissions decreased overall during the study periods.

Summary

To improve policy, prevention, and treatment services, policymakers should monitor RCLs' effects on adverse public health outcomes and researchers should consider the effects on individual and community-level characteristics. We discuss methodological challenges in conducting state-level research and provide suggestions for future studies.

State Marijuana Laws and Marijuana Use Among Sexual and Gender Minority Youth in the United States

Purpose: The purpose of this study was to explore the association between state-level marijuana policies and marijuana use among sexual and gender minority (SGM) adolescents. Methods: A secondary analysis was conducted using a nonprobability sample, the 2017 LGBTQ National Teen Survey, based on 10,027 youth who reported their marijuana use behaviors and state of residence. Random intercept multilevel models were estimated to account for between- and within-state variability. Results: State marijuana possession laws were not associated with lifetime use; however, the odds of current marijuana use were 50% greater among youth living in states with legalized marijuana possession for recreational use (adjusted odds ratio [aOR] = 1.50; 95% confidence interval [CI]: 1.21-1.86) compared with states that prohibit any possession. Lesbian, gay, bisexual, transgender, and queer victimization was associated with greater odds of lifetime (aOR = 1.98; 95% CI: 1.78-2.20) and current (aOR = 1.99; 95% CI: 1.74-2.27) marijuana use. Conclusions: State-level policies governing recreational marijuana possession are associated with current marijuana use among SGM youth. Public health approaches to control underage access to legal marijuana and mitigate substance use-related health disparities are needed.

Short-Term Effects of Recreational Cannabis Legalization on Youth Cannabis Initiation

PURPOSE

As recreational cannabis is legalized, it is critical to know the impacts of legalization on youth cannabis use. Existing research generates conflicting results and does not shed light on channels of effects. This study investigates the impacts of legalization on youth cannabis initiation and overall cannabis use prevalence.

METHODS

We used Interrupted Time Series design and data from nationally-representative repeated cross-sectional Canadian surveys spanning 16 years. The primary outcomes were cannabis initiation rates and cannabis use prevalence among youths. The secondary outcomes were self-reported age of first cannabis use, ease of cannabis access, and perception of cannabis harm among youths.

RESULTS

After legalization, cannabis initiation rate among youths was 2.7 percentage points (95% confidence interval: 1.7-3.7; p < .01) or 69% higher, although there was no significant increase in the overall prevalence of cannabis use. Furthermore, there was a 4-month delay in the average age of first cannabis use among youths aged 17-18 years (95% confidence interval: 2.6-5.5 months; p < .01). The legalization was associated with greater perception of cannabis harm but also easier access to cannabis.

DISCUSSION

The impacts of legalization on youth cannabis use after 1 year are mixed. Although we observed an increase in cannabis initiation among youths who had never used cannabis, there was no change in the overall prevalence of cannabis use, implying a possible offsetting increase in cannabis cessation among existing users. To achieve legalization's goal of reducing youth cannabis use, policy measures are needed to curb youth cannabis access and initiation.

A scoping review of school-level risk and protective factors of youth cannabis use: An application of the socio-ecological model

Risk and protective factors for cannabis use exist at various levels of influence, and the school environment can play a key role in preventing cannabis use and initiation as most youth. By using the socio-ecological model to hierarchically characterize school-specific risk and protective factors, a wholistic approach to school-based cannabis use prevention can be demonstrated. This study uses scoping review methodology to describe current research on school-level risk and protective factors of youth cannabis use. The socio-ecological model was used as a guiding framework to characterize the literature. PubMed, Embase, and Scopus were used to retrieve original research articles published between 2010 and 2020 that examined cannabis use as a main outcome of interest. Articles that examined school-related risk and protective factors within participants who were 18 years old or younger were included. Articles that met the pre-established criteria were extracted and categorised by theme based on levels of the socio-ecological framework. Four levels of risk and protective factors related to the school environment were identified (individual, interpersonal, community, and societal). A majority of school-based research examined individual and societal factors that influenced youth cannabis use. Our findings suggest most available research has focused on individual and societal school-level factors of cannabis use. A number of consistent themes were identified, however, findings were mixed and demonstrate the need for a more critical examination of research in order to understand which risk and protective factors are most influential among youth.

Prevalence and use of cannabis products and routes of administration among youth and young adults in Canada and the United States: A systematic review

BACKGROUND

The current systematic review aimed to summarize the literature on the prevalence of routes of administration and cannabis products used among youth and young adults in Canada and the United States (US).

METHODS

Five academic databases were searched in April 2020 and February 2021. Peer-reviewed articles were included if they were a population-based quantitative observational study describing the prevalence of a cannabis product or route of administration among youth and young adults in Canada or the US. Risk of bias was assessed using Hoy and colleagues' risk of bias assessment tool. A narrative review was conducted.

RESULTS

Twenty-six studies were identified for the following routes of administration: smoking (n = 16), vaping (n = 21), dabbing (n = 3), oral (n = 13), topical (n = 1); and products: dried flower (n = 2), and concentrates (n = 8). Smoking had the highest prevalence rates among youth and young adults; however, rates of use appeared to reduce over time. Conversely, prevalence of vaping appeared to increase over time. Fewer studies focused on oral or dabbed cannabis but those that did reported prevalence estimates of approximately a third among recent cannabis consumers.

DISCUSSION

The heterogeneity of cannabis routes of administration restricted our ability to collate average prevalence estimates. In jurisdictions where non-medical cannabis is legal, policymakers should provide guidance and education to youth on each type of product and routes of administration.

OTHER

Funding for this study was provided by a Canadian Institutes of Health Research (PJT-153342). The current review was registered with PROSPERO (CRD42020169275).

A Systematic Review and Narrative Synthesis of the Evolution of Adolescent and Young Adult Cannabis Consumption Before and After Legalization

PURPOSE

To systematically review evidence assessing the evolution of cannabis consumption before and after the implementation of non-medical cannabis legislation.

METHODS

MEDLINE, PubMED, PsycINFO, Scopus, and Web of Science were systematically searched for studies that examined change in cannabis consumption before and after nonmedical cannabis legislation. Data were tabulated by study design, levels of consumption, and individual subgroups. Data were analyzed using a narrative synthesis approach, considering study quality.

RESULTS

32 studies were included (11 higher quality and 21 lower quality). 40% of higher quality evidence supported an increase in postlegalization consumption (55% did not report a change and 5% reported a decrease). The increase was most evident for young adults (42% of higher quality evidence) and in the consumption in the past month (37% of higher quality evidence). There was limited supporting evidence for new users having grown in response to legalization. Based on subgroup analysis, the increase in postlegalization consumption was higher among women and those who engage in binge-drinking.

CONCLUSIONS

Higher quality evidence suggests an increase in adolescent past-month consumption of cannabis following legalization in several geographical jurisdictions. Consumption evolution prelegalization and postlegalization differed by age group and for young women and for binge drinkers. Consumption evolution differences suggest a variety of strategies might be required in efforts to lower public health impacts of cannabis consumption following legalization.

Retail cannabis environment and adolescent use: The role of advertising and retailers near home and school

Youth cannabis use is influenced by overlapping environmental contexts. We examined the associations between proximity to cannabis retailers and seeing cannabis advertisements and cannabis use behaviors in Oregon, a state with adult cannabis legalization. We used 2017 anonymous survey data from 24,154 Oregon 8th and 11th grade students. After adjustments for student and school district characteristics, advertising for 8th graders and presence of a retailer within a mile from school for 11th graders were associated with cannabis use and perceived harm. Additional policy efforts may further reduce youth exposure to cannabis.

Licensed and unlicensed cannabis outlets in Los Angeles County: the potential implications of location for social equity

Background

Cannabis social equity programs intend to redress inequities experienced by low income and Black, Indigenous, and People of Color (BIPOC) during cannabis prohibition in the United States. In Los Angeles County (LA), the approach is to increase cannabis outlet licensure and employment for low income and BIPOC communities. Monitoring locations of both licensed and unlicensed outlets over time is critical to informing how local social equity programs may affect communities.

Methods

We identified locations of licensed and unlicensed cannabis outlets in LA, from February to April 2019 and again from March to April 2020, and calculated the number and type of outlets by socio-demographic characteristics of census tracts (race/ethnicity, poverty, education, unemployment) using the 2013–2017 American Community Survey 5-year estimates.

Results

Licensed outlets increased in LA from 162 in 2019 to 195 in 2020; unlicensed outlets decreased from 286 to 137 over the same time period. In 2020, more licensed outlets were in tracts with majority white residents and adults with at least a bachelor’s degree; fewer licensed outlets were in tracts with larger Latinx or Black populations, whereas 71% of unlicensed outlets in 2020 were in low-income tracts, and more unlicensed outlets were in predominately Latinx tracts, high poverty and high unemployment tracts, and tracts with more single female-headed households.

Conclusions

Neighborhood-level analyses are an important first step, but more data are needed for comprehensive evaluations of social equity programs—from individual businesses to the communities living nearby—to understand the impacts on low income and BIPOC populations.

Perceived access to cannabis and ease of purchasing cannabis in retail stores in Canada immediately before and one year after legalization

Background: Canada legalized non-medical cannabis in October 2018. Little research has examined the change in perceived access to cannabis after legalization in Canada, including the perceived ease of purchasing cannabis in a legal market.Objectives: To: 1) describe changes in perceived ease of access to cannabis before and one year after legalization; 2) examine associations between perceived ease of cannabis access and cannabis use; and 3) examine associations between perceived ease of purchasing from cannabis stores and cannabis use.Methods: Repeat cross-sectional data come from Canadian respondents aged 16-65 (50% male) in August-October 2018 (n = 10,057) and September-October 2019 (n = 15,256). Respondents were recruited through commercial online panels. Multivariable logistic regression models examined correlates of perceived proximity to retail stores, ease of access, and ease of purchasing from retail stores.Results: Canadians who do not consume cannabis were more likely to report "easy" access to cannabis in 2019 than in 2018 (55% vs. 42%; AOR = 1.80:1.66,1.96). All cannabis consumer groups were more likely to report living 15 minutes or less from a retail store in 2019 than 2018, but the association was strongest among non-consumers in 2019 vs 2018 (AOR = 2.01:183,2.21 vs. AOR = 1.33:1.03,1.73 for daily consumers). Non-daily and daily cannabis consumers were more likely to report it was easy to purchase from an illegal (AOR ranged 1.58-2.22) or legal (AOR ranged 1.31-1.39) store than non-consumers in 2019.Conclusion: Most cannabis consumers and non-consumers perceived access to cannabis as 'easy' before legalization and the percentage increased one year after legalization.

Municipal regulation of cannabis and public health in Canada: A comparison of Alberta, Ontario, and Québec

Canada legalized nonmedical cannabis in October 2018, but significant variations in municipal regulations exist. This study explored the variations that exist and pondered their potential public health consequences. A comparative analysis was completed on the regulations and guidelines that addressed retailers' location and public consumption in the municipalities of Alberta, Ontario, and Québec. Municipal regulations that addressed the location of retailers were more numerous and extensive in Alberta and Ontario (in the context of provincial private retail models) than in Québec (government-based model). Municipalities in Alberta added more restrictions to public consumption laws as compared to municipalities in Ontario and in Québec. These additions were made to Alberta's and Ontario's provincial-level smoking and vaping bans which used tobacco-inspired frameworks, and to Québec's ban on smoking and vaping in all public spaces. The comparative analysis showed the importance of considering municipal cannabis regulations when studying the impact of legalization, given the significant variations that exist. Policy makers should be made aware of these variations in the regulation of cannabis in order to limit health harms and further social inequalities.

Societal Costs and Outcomes of Medical and Recreational Marijuana Policies in the United States: A Systematic Review

Significant support exists in the United States for legalization of marijuana/cannabis. As of 2021, 36 states and four territories approved the legalization of medical cannabis via medical marijuana laws (MMLs), and 15 states and District of Columbia (DC) have adopted recreational marijuana laws (RMLs). We performed structured and systematic searches of articles published from 2010 through September 2021. We assess the literature pertaining to adolescent marijuana use; opioid use and opioid-related outcomes; alcohol use; tobacco use; illicit and other drug use; marijuana growing and cultivation; employment, earnings, and other workplace outcomes; academic achievement and performance; criminal activity; perceived harmfulness; traffic and road safety; and suicide and sexual activity. Overall, 113 articles satisfied our inclusion criteria. Except for opioids, studies on use of other substances (illicit drugs, tobacco, and alcohol) were inconclusive. MMLs and RMLs do not generate negative outcomes in the labor market, lead to greater criminal activity, or reduce traffic and road safety.

Recreational Marijuana Legalization and Co-use With Alcohol Among Adolescents

INTRODUCTION

Little is known about the possible impacts of recreational marijuana legalization on alcohol and marijuana co-use among underage youth. This study examines the association between recreational marijuana legalization in California in 2016 and alcohol and marijuana co-use among adolescents. Additional analyses investigate the associations between recreational marijuana legalization and co-use among past 30-day drinkers and marijuana users and the frequency of alcohol and marijuana use among co-users.

METHODS

This study used annual cross-sectional data from 7th, 9th, and 11th graders (N=3,319,329) who participated in the California Healthy Kids Survey from 2010-2011 to 2018-2019. Measures included past 30-day alcohol and marijuana use and student demographic characteristics, survey year, pre-post recreational marijuana legalization, and urbanicity. Multilevel regression analyses were conducted in 2021.

RESULTS

Recreational marijuana legalization was associated with greater odds of past 30-day alcohol and marijuana co-use in the total sample (OR=1.06, 95% CI=1.05, 1.07). Recreational marijuana legalization was more strongly associated with co-use among adolescents who reported past 30-day alcohol use (OR=1.58, 95% CI=1.52, 1.62) and heavy drinking (OR=1.25, 95% CI=1.21, 1.29) but was inversely related to co-use among past 30-day marijuana users (OR=0.76, 95% CI=0.74, 0.78). Among past 30-day co-users, there was a positive association with the frequency of marijuana use (β=0.36, SE=0.07).

CONCLUSIONS

Recreational marijuana legalization may increase the risk of alcohol and marijuana co-use among adolescents. Greater restrictions on the numbers of alcohol and marijuana retail outlets and hours of operation and advertising and higher taxes on alcohol and marijuana products may help reduce the availability of these substances to adolescents.

Adolescents' Marijuana Use Following Recreational Marijuana Legalization in Alaska and Hawaii

Alaska and Hawaii, the only two noncontiguous states in the United States, have different marijuana policy environments. Alaska enacted recreational marijuana legalization (RML) in 2014, whereas recreational marijuana is still illegal in Hawaii. This study analyzed how RML affects adolescents' marijuana use (MU) by comparing two states. We used data from 2 states (Alaska and Hawaii) from the Youth Risk Behavior Survey, 2009 to 2019 years (N = 35 467). The trends of lifetime MU and current MU were examined. Using difference-in-differences analysis models, this study investigated whether RML increased lifetime and current MU in Alaska compared with Hawaii after adjusting for socioeconomic characteristics. Both lifetime and current MU prevalence among adolescents in Alaska increased after RML, while both rates in Hawaii gradually decreased. The rate of lifetime MU in Alaska was significantly increased after RML (odds ratio [OR] = 1.29) compared with Hawaii. Similarly, the current MU among adolescents in Alaska was significantly increased compared with that in Hawaii (OR = 1.34). Both lifetime and current MU were increased following RML in Alaska, suggesting that RML may affect the increase of MU among adolescents.

The importance of psychology for shaping legal cannabis regulation

Different patterns of cannabis use can be traced directly back to different interactions between 2 types of variables: pharmacological and environmental. As legal cannabis expands in the U.S. and around the world, state and national regulatory agencies are gaining control over these variables. Specifically, regulatory agencies are increasingly capable of altering (a) the pharmacological properties of cannabis products and (b) the way these products are distributed to the population. Consequently, cannabis regulatory agencies are in a unique position to use evidence from psychological science to alter cannabis consumption patterns in ways that mitigate potential harm to public health. However, most state-level legal cannabis regulatory systems in the U.S. are not yet evidence-based or public health-oriented. This applied review and commentary draws on evidence from the psychological science literature to help regulators better understand the types of behaviors they must address and guide empirically supported regulation of THC-laden cannabis, whether used putatively for medical or recreational reasons. This review is organized into 3 parts that correspond to the 3 primary agents within the cannabis regulation ecosystem: (a) the cannabis consumer, (b) the cannabis industry, and (c) the cannabis regulatory agency. Within this structure, the review addresses critical psychological variables that drive cannabis consumer and industry behaviors and discusses how regulatory agencies can use this information to protect public health. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Retail Availability of Recreational Marijuana and Alcohol in Oregon Counties and Co-Use of Alcohol and Marijuana and Related Beliefs among Adolescents

Objective: We investigated whether recreational marijuana legalization (RML) in Oregon in 2015 and recreational marijuana and alcohol retail outlet density levels in Oregon counties were associated with increased alcohol and marijuana co-use and beliefs supportive of alcohol and marijuana use among adolescents. Method: We conducted secondary analyses of biennial data collected from 11th graders who participated in the Student Wellness Survey (SWS) in 36 Oregon counties from 2010 to 2018 (N = 71,870). Multi-level logistic regression analyses assessed changes in past-30-day co-use of alcohol and marijuana, and alcohol- and marijuana-related beliefs after RML in counties with low, medium, and high densities of licensed recreational marijuana and alcohol retail outlets. We used post-RML 2016 and 2018 SWS data to examine whether beliefs accounted for any relationship of recreational marijuana and alcohol outlet density with alcohol and marijuana co-use. Results: We found a significant post-RML increase in past-30-day alcohol and marijuana co-use in 2016 in counties with the highest density of recreational marijuana and alcohol retail outlets. There were significant post-RML increases in perceived risk and parent approval of alcohol and marijuana use. Analyses with 2016 and 2018 SWS data indicated that the relationship between level of recreational marijuana and alcohol retail outlet density and past-30-day alcohol and marijuana co-use was accounted for beliefs about marijuana and alcohol availability, approval by parents, and risk. Conclusion: RML and greater retail availability of recreational marijuana and alcohol were positively associated with alcohol and marijuana co-use among adolescents, and with beliefs favorable to alcohol and marijuana use.

Recreational Marijuana Legalization and Use Among California Adolescents: Findings From a Statewide Survey

OBJECTIVE

The legalization of recreational marijuana use and retail sales raises concerns about possible effects on marijuana use among adolescents. We evaluated the effects of recreational marijuana legalization (RML) in California in November 2016 on use among adolescents and investigated subgroup differences in these effects.

METHOD

We analyzed data from successive cross-sectional samples of 7th, 9th, and 11th grade students (N = 3,330,912) who participated in the California Healthy Kids Survey from 2010-2011 to 2018-2019. Participants reported grade, sex, ethnicity, race, and lifetime and past-30-day marijuana use.

RESULTS

Multilevel analyses showed that RML was associated with increases in the likelihood of lifetime (odds ratio = 1.18, 95% CI [1.15, 1.21], p < .01) and past-30-day marijuana use (odds ratio = 1.23, 95% CI [1.20, 1.26], p < .01) relative to previous downward trends. RML was more strongly associated with increases in prevalence of marijuana use among 7th versus 9th and 11th graders, females versus males, non-Hispanic versus Hispanic youth, and White versus African American, American Indian/Native Alaskan, and multiracial youth. Overall, RML was not significantly associated with frequency of past-30-day use among users, although stronger positive associations between RML and frequency of use were found for 11th graders, Asian Americans, and African Americans. The association was weaker for females.

CONCLUSIONS

RML in California was associated with an increase in adolescent marijuana use in 2017-2018 and 2018-2019. Demographic subgroup differences in these associations were observed. Evidence-based prevention programs and greater local control on retail marijuana sales may help to reduce marijuana availability and use among adolescents.

Examining Associations Between Licensed and Unlicensed Outlet Density and Cannabis Outcomes From Preopening to Postopening of Recreational Cannabis Outlets

BACKGROUND AND OBJECTIVES

To expand on epidemiologic studies examining associations between the legalization of recreational cannabis and use among young adults, we examined the associations between licensed and unlicensed cannabis outlet density and cannabis outcomes.

METHODS

A total of 1097 young adults aged 21 and older living in Los Angeles County were surveyed before licensed recreational cannabis outlets opened (Time 1: July to December 2017) and after (Time 2: July 2018 to June 2019). Using a database of open licensed and unlicensed cannabis retailers to calculate individual-level cannabis outlet density measures, we examined associations between outlet density within a 4-mile radius of participants' residences with Time 2 outcomes of any past-month use, daily use, intentions to use, quantity used, consequences, and cannabis use disorder (CUD) symptoms.

RESULTS

After controlling for demographic factors and cannabis outcomes at a time point prior to their opening (Time 1), licensed cannabis outlets were associated with young adults' cannabis use, heavy use, and intentions, and unlicensed outlets were associated with young adults' heavy cannabis use and CUD symptoms.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

This study expands beyond studies of outlet prevalence to find that, after controlling for outcomes 1 year prior, licensed and unlicensed outlets were associated with young adults' cannabis outcomes. The current study is among the first to find associations between cannabis use outcomes and density of cannabis outlets among young adults using data from two time points: preopening and postopening of recreational cannabis retailers. Findings can inform policies around the density and placement of cannabis outlets. (Am J Addict 2020;00:00-00).

Validation of secondary data sources for enumerating marijuana dispensaries in a state commercializing marijuana

OBJECTIVES

To assess 1) the validity of online crowdsourcing platforms in enumerating licensed brick-and-mortar marijuana dispensaries and 2) the validity of state licensing directory and online crowdsourcing platforms in enumerating active brick-and-mortar marijuana dispensaries in California.

METHODS

We obtained business lists from California Bureau of Cannabis Control (BCC) licensing directory and three online crowdsourcing platforms (Weedmaps, Leafly, and Yelp) in May 2019. Calls were made to verify street address, operation status, dispensary category (recreational-only, medical-only, recreational & medical), and presence of storefronts in May-July 2019. Validity measures, including sensitivity, specificity, positive predictive value, and negative predictive value, were calculated when applicable.

RESULTS

In identifying licensed dispensaries in BCC, Leafly had the highest sensitivity (.66) and Yelp had the highest specificity (.87). The dispensary category posted on online crowdsourcing platforms in over 25 % licensed dispensaries and the dispensary category claimed in call verification in over 10 % licensed dispensaries disagreed with the approved category in BCC. There were 2121 businesses combined from BCC and online crowdsourcing platforms, among which 826 were verified to be active brick-and-mortar dispensaries. Weedmaps had the highest sensitivity (.80) and Yelp had the highest negative predictive value (.74) in identifying verified dispensaries. Weedmaps overall had the highest sensitivity in all three dispensary categories. Weedmaps had the highest sensitivity in more populated counties whereas BCC had the highest sensitivity in less populated counties.

CONCLUSIONS

Each secondary data source has strengths and limitations. The findings inform surveillance and research regarding how to best strategize data use when resources are limited.