Psychometric analysis of the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) in an inpatient sample

As there is a high prevalence of social fears in psychotherapeutic inpatients, the present study aimed to examine the scales in an inpatient sample. The sample consisted of 823 inpatients: 190 diagnosed with psychometric properties of the social phobia, 129 with other anxiety disorders, and 504 with other clinical disorders. Both scales show high levels of internal consistency and test-retest reliability. Correlations with other symptom measures indicate adequate convergent, but inadequate discriminative validity. Although the scales discriminate between the different clinical samples, classification performance is low and decreases with higher comorbidity. Thus, the differential diagnostic utility of the questionnaires remains questionable.