The Validity of Truant Youths' Marijuana Use and Its Impact on Alcohol Use and Sexual Risk Taking.

Few studies investigating the validity of marijuana use have used samples of truant youth. In the current study, self-reports of marijuana use are compared with urine test results for marijuana to identify marijuana underreporting among adolescents participating in a longitudinal Brief Intervention for drug-involved truant youth. It was hypothesized that marijuana underreporting would be associated with alcohol underreporting and engaging in sexual risk behaviors. The results indicated marijuana underreporting was significantly associated with self-denial of alcohol use, but not associated with sexual risk behavior. Also, there was an age effect in marijuana use underreporting such that younger truant youth were more likely to underreport marijuana use, compared to older truant youth. Implications for policy and future research are discussed.