Evaluation of Availability of Survey Data About Cannabis Use

Abstract

Importance: In response to increasing public support for cannabis legalization, understanding associations of state and federal policy changes related to cannabis legalization with patterns of cannabis use is important. A challenge for public health monitoring and research is significant variation in data availability related to cannabis use behaviors and perceptions across and within states and over time, including the availability of prelegalization vs postlegalization data.

Objective: To review data available on cannabis use and related behaviors over time in Massachusetts and the US.

Design, setting, and participants: This case series examined state and national surveys on public health and related behaviors and outcomes to review availability of cannabis-related data for Massachusetts for 8 key indicators over time. Additionally, the Behavioral Risk Factor Surveillance System (BRFSS) and Youth Risk Behavior Surveillance System for all states were reviewed. The analysis was conducted between February 1, 2019, and March 18, 2020.

Exposures: Surveys that enable state-level estimation of cannabis use and related behaviors.

Main outcomes and measures: Eight key indicators related to cannabis use behaviors and perceptions: lifetime cannabis use, age of initiation, frequency of use, location of use, method of use, source of cannabis, perceptions of cannabis, and reason for use (ie, medical vs nonmedical).

Results: There were 7 surveys that monitored cannabis use and related behaviors in Massachusetts for adolescents and adults. No surveys monitored all 8 indicators of interest, and availability over time was limited. In the most recent BRFSS, 24 states asked cannabis-related questions, meaning BRFSS data on cannabis use was lacking for more than half of the US adult population. In the Youth Risk Behavior Surveillance System, 36 states asked standard cannabis questions; most other states had at least 1 question related to cannabis use and frequency.

Conclusions and relevance: These findings of limitations of existing surveys, and particularly the lack of national questions in the BRFSS and Youth Risk Behavior Surveillance System, suggest that available data have substantial limitations for monitoring cannabis use. As cannabis policy changes continue, there is a need to remain focused on the availability of high-quality data sources that allow for critical public health research.

Figure.. Cannabis Questions Available in National Surveys

A, The most recent questionnaire available used to determine questions. Alaska and Hawaii not shown; Alaska used the national marijuana module, and Hawaii did not have cannabis-related questions. Ohio added the national marijuana module in 2018. B, Other includes the Massachusetts questionnaire, which includes a question related to 30-day use of marijuana, but does not include 30-day frequency of use; 7 states (ie, Alabama, Georgia, Indiana, Mississippi, New Jersey, Ohio, South Dakota) did not achieve adequate response rates to report population weighted estimates in 2017.