Developing a Brief Version of the Social Thoughts and Beliefs Scale (STABS) Using Item Response Theory

Cognitions play a central role in the maintenance of social anxiety disorder (SAD). The aim of the present study was to develop a brief version of the social thoughts and beliefs scale (STABS) that can be used in clinical trials and experience sampling studies in which multiple repeated measures (e.g., weekly or daily measurements) are utilized. Our sample (n = 361) included both individuals diagnosed with SAD (n = 108) and non-anxious controls (n = 253). We used item response theory analyses to examine items of the STABS and kept only items which differentiated between 4 levels of SAD-related cognitions between the 5th and 95th percentiles of scores. This strategy resulted in a brief, seven-item scale—the mini-STABS. We then compared the mini-STABS with the full-length, 21-item STABS, as well as examined convergent and divergent validity for the brief measure. Results indicated that the mini-STABS was highly correlated with the 21-item STABS, and demonstrated similar patterns of associations with convergent and divergent measures compared to the 21-item STABS. These findings suggest that the mini-STABS is a psychometrically sound brief version of the STABS that provides similar information using fewer items. Implications for assessment of SAD are discussed.