Quantitative data.

Both anxiety sensitivity (AS) and experiential avoidance (EA) have been linked to social anxiety disorder (SAD). However, previous studies did not consider their joint variance and the heterogeneity of SAD. In this mixed methods cross-sectional survey, we examined 121 online participants (age range: 16–70 years) who self-reported as socially anxious. We compared AS and EA levels in individuals with a primary fear of noticeable anxiety symptoms vs. behaving ineptly. AS and EA were highly prevalent across the sample. Surprisingly, the noticeable symptoms subtype showed slightly lower AS and EA levels than the inept behavior subtype. The noticeable symptoms subtype scored notably lower on social anxiety measures (mean = 69.8) than the inept behavior subtype (mean = 89.3). EA was uniquely associated with social anxiety in both subtypes, while AS was uniquely associated with social anxiety only in the inept behavior subtype. The joint variance explained substantially more of the noticeable symptoms subtype’s social anxiety (32.5%) compared to the inept behavior subtype’s (9.4%). Qualitative themes aligned with these findings, indicating a self-reinforcing dynamic between high AS, high EA, and social anxiety symptoms. Potential clinical implications are discussed. Future research should examine causality in the AS-EA-SAD dynamic, considering the heterogeneity of SAD.