Peer substance use and deviance is linked with risk for adolescent substance use (Trinidad et al., 2018; Buu et al., 2009). The ABCD protocol includes a 9-item Peer Group Deviance instrument that was modified from the PhenX (https://www.phenxtoolkit.org/) peer substance use questionnaire, which include items from the MTF study (Johnston et al., 2015, Johnston et al., 1988). For each item, participants are asked the initial stem: “how many of your friends…?” with queries for drink alcohol (full beer, wine or liquor), get drunk, have problems with alcohol or other drugs, use cannabis, smoke cigarettes, use inhalants (gas, glue, nitrous oxide), use other drugs like cocaine, downers or LSD, and sell or give drugs to others. The item responses are on a 5-point scale: “none,” “a few,” “some,” “most” or “all.” One additional question was added to address the rising use of alternative nicotine delivery devices: use other tobacco products like e-cigarettes, pipes or hookah (Breland et al., 2016, Breland et al., 2014; Lopez et al., 2016). Youth are only asked questions about peer substance use for those substances they endorsed having heard of at the beginning of the substance use interview.
