Explaining the effects of treatment components in internet-based cognitive-behavioral treatment for social anxiety disorder: A factorial mediation analysis.

BACKGROUND

More understanding of how internet-based cognitive-behavioral programs (ICBT) for social anxiety disorder (SAD) work could help further optimize treatment. This paper examines the mediational role of knowledge of SAD, negative social cognitions, self-focused attention, avoidance of social situations, and use of safety behaviors in explaining the main components of ICBT for SAD (psychoeducation, cognitive restructuring, attention training, and exposure).

METHODS

In a 24 factorial trial, 464 participants diagnosed with SAD were randomized to 16 combinations of components of a minimally-guided ICBT program for SAD (Shyne) for 8 weeks, allowing us to compare the main effect for the presence of each component (n = 232) against its absence (n = 232). Mediation was investigated using the joint significance test and path analysis of indirect effects.

RESULTS

Previous evidence that psychoeducation and exposure are the most active components was replicated. In single mediator models, knowledge gain mediated the effects of psychoeducation, and reduced use of safety behaviors mediated the effect of exposure. Contrary to a priori hypotheses, the effect of exposure was not mediated by avoidance of social situations, although decreased avoidance was significantly associated with better outcomes. Exploratory analysis with multiple mediator models showed that the main effect of exposure was mediated by reduced use of safety behaviors and reduced negative social cognitions. Self-focused attention was consistently identified as an inert mechanism of change.

CONCLUSION

Reductions in use of safety behaviors, avoidance, and negative social cognitions (in this order) are important mechanisms in explaining the effects of psychoeducation and exposure components for treating SAD.