Are Changes in Negative Cannabis Expectancies, Peer Approval, and Perceptions of Dangerousness of Driving After Cannabis Use Associated with Changes in Instances of Driving After Cannabis Use Following a Mobile-Phone Based Intervention?

Objective: Driving after cannabis use (DACU) has become an increasing public health concern nationwide. Although previous research has linked perceived peer approval, perceptions of dangerousness, and negative effect expectancies to DACU, no previous work has examined whether these constructs can be successfully targeted in an intervention or whether changes in these variables lead to changes in DACU. The present study is a secondary data analysis to investigate within-subject change and potential mechanisms of change in a pilot trial for a mobile phone-based intervention shown to significantly reduce DACU over time. Method: Participants were 66 emerging adults who completed the mobile-based intervention and provided 3-month follow-up data. Participants completed measures that assessed rates of DACU, negative cannabis expectancies, perceptions of dangerousness, and perceived peer-approval. Results: Results indicated that negative effect expectancies significantly increased from baseline to three-month follow-up, while perceived peer approval for DACU significantly decreased from baseline to three-month follow-up. Though significant within-subject change was found for all variables of interest, none of the variables of interest significantly mediated changes in instances of DACU over time. The results of the current study suggest that key variables associated with DACU-perceived peer approval and negative cannabis expectancies can be successfully targeted in a mobile-based brief intervention. Conclusions: Continued research investigating moderators and mediators of intervention outcomes is warranted.