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; n = 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 (p < .001). During CBT, within-individual improvements in emotion regulation significantly predicted later LSAS-SR reductions (p = .041, pseudo-R2 = 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.
Keywords: Emotion regulation; cognitive behavior therapy; social anxiety disorder; therapeutic processes.