Introduction: social anxiety is a pervasive psychological issue. While evidence-based treatments are available, they suffer from potential barriers such as lengthy wait-list times, overestimated effects, and a potential decline in effectiveness. The present study posits that committed momentum therapy (CMT), a novel unguided self-help ultra-brief treatment, can surpass these barriers. The present study was an ultra-brief two timepoint study (pretreatment and post-treatment) that sought to compare CMT with a control condition and graduated exposure therapy across five days. The study hypothesised that CMT would result in significantly lower post-treatment social anxiety scores than GET and the control conditions. Moreover, it hypothesised that CMT would result in lower post-treatment ratings of small and moderate exposures than GET, i.e., that they behaviours would be easier than previously rated. Method: 71 participants participated in survey 1 (49 females, mean age =30.20, SD = 17.44). Participants were randomly allocated to either the CMT, GET, or control condition. In survey 1, participant social anxiety was measured with the Liebowitz social anxiety scale self-report. Participants allocated to CMT and GET were given worksheets of behaviours and activities to conduct; they identified varying difficulties of behaviour using the subjective units of distress. During survey 2, participants took the Liebowitz scale again and CMT and GET participants rated how difficult the small and medium exposure behaviours were. Results: a linear mixed model suggested that there was a significant interaction effect between condition and treatment at the post-treatment level. However,CMT did not differ from GET or the control conditions significantly. A Bayesian MannWhitney t-test examining whether CMT differed in rating small exposures compared to GET suggested that the results were more likely under the null hypothesis. A Bayesian t-test examining whether CMT differed in rating medium exposures compared to GET suggested
that the results were more likely under the null hypothesis. Discussion: overall, no hypotheses were supported. However, CMT produced a significant reduction of social anxiety at the post-treatment level. The results suggested that CMT had moderate evidence for improving social anxiety at the post-treatment level, however, future research is required to ascertain comparative effectiveness. Implications, such as pioneering a novel intervention and supporting prior ultra-brief intervention, and limitations, such as attrition rate, are discussed as they relate to prior literature.