Return of negative interpretation bias after positive interpretation training as a dynamic predictor of treatment outcome in fear of public speaking.

Despite various efforts in the field, no consistent predictors of treatment outcome in anxiety disorders have been identified. Based on the Dynamic System Theory, this study proposes a novel, dynamic predictor of treatment outcome in those with public speaking anxiety. It was assessed whether speed of return to one's interpretation bias equilibrium after an experimentally-induced perturbation (i.e., interpretation training targeting negative interpretation bias as a critical maintaining factor for anxiety) predicts subsequent outcome to online exposure treatment. Women with subclinical public speaking anxiety (N = 100, M age = 23.13, SD = 3.89) were randomly allocated to a positive interpretation training (n = 50) or a neutral interpretation training (n = 50). Dynamic changes in negative interpretations were measured using Experience Sampling Method. Later, participants followed an online one-session exposure therapy for public speaking anxiety. Positive interpretation training resulted in a stronger reduction in negative interpretations compared to the neutral interpretation training. Fear of public speaking decreased from before to after the exposure therapy. Consistent with our central hypothesis, results showed that slower return to one's interpretation bias equilibrium after the positive interpretation training was associated with a greater decline in fear of public speaking after exposure treatment. These results show the potential of a dynamic approach in predicting treatment outcome in public speaking anxiety. This study contributes to the field of clinical psychology, as finding more reliable predictors of treatment outcome before the start of therapy could contribute to the efficiency of care delivery.