Although computer delivered brief interventions (CDBIs) have been effective in reducing alcohol use, few studies have examined which components of CDBIs are most associated with drinking reductions. The current factorial trial deconstructed a brief alcohol intervention into component parts to identify main and interaction effects on drinking outcomes. Participants (N = 352) were randomly assigned to 1 of 16 possible combinations of four dichotomous (present vs. absent) CDBI components for which theoretical and empirical support was available: empathic reflections, motivational strategies, a spoken voice, and an animated narrator. We measured main and interaction effects of these components on the primary outcome of self-reported mean drinks per day at 1- and 3-month follow-up, as well as on secondary outcomes, including binge drinking, intentions to reduce drinking, and alcohol consequences. Participants reduced drinking across all alcohol use indices over the 3-month assessment period. These effects were stronger for participants who were exposed to motivational strategies, F = 7.7, p < .001. Empathic reflections, use of a spoken voice, and use of an animated narrator were not associated with reductions in alcohol use, either as main effects or in interaction with other factors. Results suggest that CDBIs using motivational strategies are effective in reducing alcohol use. However, empathic reflections and lifelike characteristics (e.g., narrator, voice) may operate differently in CDBIs than they do in person-delivered interventions. More research is needed to better understand how these (or other factors) may influence efficacy. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Trial registration: ClinicalTrials.gov NCT02952872.