Improvements in emotion regulation during cognitive behavior therapy predict subsequent social anxiety reductions.

Individuals with social anxiety disorder (SAD) experience overall emotion regulation difficulties, but less is known about the long-term role of such difficulties in cognitive behavior therapy (CBT) for SAD. Forty-six patients with SAD receiving internet-delivered CBT, and matched healthy controls (HCs;  = 39), self-reported the Difficulties in Emotion Regulation Scale (DERS), Liebowitz Social Anxiety Scale (LSAS-SR), and participated in anticipatory speech anxiety behavioral experiments. Patients were measured at seven time points before, during and after CBT over a total period of 28 months, and HCs at two timepoints. Disaggregated growth curve models with a total of 263 observations were used, as well as intra-class correlation coefficients and regression models. Patients' LSAS-SR and DERS ratings were reliable (ICC = .83 and .75 respectively), and patients, relative to controls, showed larger difficulties in emotion regulation at pre-treatment ( < .001). During CBT, within-individual improvements in emotion regulation significantly predicted later LSAS-SR reductions ( = .041, pseudo- = 43%). Changes in emotion regulation may thus be important to monitor on an individual level and may be used to improve outcomes in future developments of internet-delivered CBT.