Development and Evaluation of an Online Intervention for Reducing Hostile Interpretation Bias: A Randomized Controlled Trial

Hostility is a trait-level construct characterized by a gener-ally suspicious and cynical view of other people that results in a tendency to interpret ambiguous social situations in hostile or threatening ways. Cognitive behavioral treat-ments for hostility have high dropout rates, which may be due to hostile beliefs interfering with treatment engage-ment. As such, there is a need for an alternative approach to prevent dropout and enhance engagement. The current study therefore developed and tested a 1-session, 40 -minute online intervention targeting hostility. It was hypothesized that the hostility intervention would be rated as acceptable as indexed by self-report and completion rates. It was also hypothesized that the hostility interven-tion would be associated with greater reductions in hostil-ity as compared to a control intervention. Finally, it was hypothesized there would be indirect effects of intervention condition on anger and aggression via changes in hostility. Undergraduates (N = 101) who reported elevated hostility and hazardous alcohol use were randomized to complete either the hostility intervention or a control condition tar-geting physical health habits. Results showed that individ-uals randomized to the hostility intervention found the intervention to be highly acceptable and all participants completed the intervention in its entirety. The hostility intervention was associated with significantly faster reduc-tions in hostile interpretations than the control condition with medium to large effects. There were significant indi-rect effects of intervention condition on month one follow-up anger and aggression via changes in hostile cog-nitions. This proof-of-concept study provides initial evi-dence that a brief, single-session intervention may be a promising approach for reducing hostility and its correlates.