Perceived peer cannabis use was coded as the response to an item: When you were 12–17, how many of your best friends used marijuana? (0 = none, 1 = a few, 2 = most, 3 = all; categories representing “most” and “all” were combined as the latter was only endorsed by 35 individuals); To minimize recall bias, peer use reported at the last assessment was used for those aged 12–17 (n=818), and at the assessment closest to age 12–17 for subjects aged 18 and older (349, although 91% were 18–21 years of age).
