Session: Adolescent Marijuana Use in Washington, Oregon, and Colorado (Society for Prevention Research 24th Annual Meeting)

In 2013, 40% of 9th-12th graders reported lifetime use of marijuana, and 23% reported past 30-day use. Given recent changes in marijuana policies at the state level, it is important to examine the nature of marijuana use among adolescents, and how it is changing. It is widely suspected that adolescent marjijuana use will increase as a result of changes in state policies, and also that there will be a greater diversity of methods used to consume marijuana. Factors influencing changes in marijuana use may relate to community norms, risk perceptions, and ease of access. This symposium includes three studies based on population-based samples of youth in Colorado, Washington, and Oregon, all of which have passed laws "legalizing" marijuana.This research is highly policy relevant given the number of states currently planning ballot initiatives to legalize marijuana.

In the first presentation, we use data from Washington State's Healthy Youth Survey (10th and 12th graders) to examine trends in substance use (marijuana, alcohol, and tobacco) and perceived availability of those substances among adolescents from 2004-2014. We specifically explore differences by race/ethnicity.

In the second presentation, we examine Colorado high school students' use of alternative modes of marijuana consumption, including edibles and vaporizers. We examine how use of alternative methods is associated with risk perceptions, use of alcohol and cigarettes, and demographic factors, including race/ethnicity, sex, LGBT status.

In the third presentation, we will examine the associations between county-level voting on a ballot initiative to legalize marijuana and adolescents' (8th and 11th graders) risk perceptions about marijuana as well as their marijuana use. Data are from the Oregon Healthy Teen survey. This presentation will shed light on how adults' community-level norms are related to adolescents' marijuana use.

An expert in substance use epidemiology will serve as a discussant, thereby identifying common themes across presentatons, implications for prevention and policy, and areas for future research.