Evaluating the Social Functioning Scale modified for use in individuals at clinical high-risk for psychosis

Background: Social functioning deficits occur prior to the onset of psychosis and predict conversion to psychosis in clinical high-risk (CHR) populations. The Social Functioning Scale (SFS), a self-report measure of social functioning, is widely used in adults with psychosis but has not been tailored to CHR individuals. CHR syndromes overlap with the adolescent/young-adult developmental period, a time with unique social demands and contexts. The current study evaluates a modified version of the SFS in CHR individuals. Methods: Two independent samples of CHR participants (n = 84 and n = 45) and non-CHR participants (n = 312 and n = 42) completed the SFS and a psychosis-risk interview. Resulting factors were compared across diagnostic categories (CHR, Major Depressive Disorder, Generalized Anxiety Disorder) and community controls (CC) who were not excluded for any psychopathology except psychosis, depression, and anxiety. CHR participants completed scales of negative symptoms, global social and role functioning, cognition, and finger tapping as measures of convergent and divergent validity. Results: Exploratory factor analysis identified three SFS factors (RMSEA = 0.05) which demonstrated reliability in a confirmatory analysis in an independent sample: Recreation (α = 0.82), Nightlife (α = 0.85), and Interpersonal (α = 0.69). Factors and their composite score demonstrated increased social deficits in CHR compared to CC and depression groups and showed expected convergent (r's = 0.30–0.54) and divergent (r's = −0.004–0.26) validity with appropriate measures. Conclusions: These findings suggest that there are reliable, valid, and developmentally relevant categories of social behavior within the SFS that differentiate between CHR and MDD or CC individuals. Recommendations for future work with CHR populations are included.