Mediators of transdiagnostic group cognitive behavior therapy.

The efficacy of cognitive-behavioral therapy (CBT) for anxiety is well established. Investigations into the mechanisms of change in CBT report changes in cognitive vulnerabilities mediating improvements over the course of treatment. As anxiety disorders share certain risk factors, there is a trend toward CBT emphasizing these vulnerabilities, including negative affectivity (NA) and also more specific constructs such as anxiety sensitivity (AS) and intolerance of uncertainty (IU). The purpose of this investigation was to analyze potential mediators of anxiety reduction over the course of transdiagnostic group CBT. NA, AS, and IU all decreased over the course of treatment. Among the potential mediators, change in NA had a significant relationship with change in anxiety but change in AS and change in IU did not. Neither the main effect of primary diagnosis nor the interactions between potential mediators and primary diagnoses were significant, indicating that there were no differential changes in anxiety or the potential mediators across primary diagnoses. Results strongly point toward NA as an overarching mediator of anxiety reduction during transdiagnostic group CBT.