Validation of the social functioning scale: Comparison and evaluation in early psychosis, autism spectrum disorder and social anxiety disorder.

Social functioning is an important component of mental disorders for assessment and treatment. There is no recognised self-report instrument to measure social functioning across disorders where social impairment is significant. The Social Functioning Scale (SFS) has, however, been used to assess social functioning in psychotic disorders, including Schizophrenia and Early Psychosis. The current study investigated the reliability, validity and sensitivity of the SFS in Early Psychosis, Autism Spectrum Disorder (ASD), Social Anxiety Disorder (SAD) and neurotypical control populations. As expected, all clinical groups showed significant impairment on the total and sub-scale scores of the SFS. The SFS showed good internal consistency and concurrent validity for people diagnosed with SAD and Early Psychosis and a similar factors structure was found for these groups. Participants with ASD reported a relatively low internal consistency and poor concurrent validity, as well as a three-component solution. The SFS has also showed a good sensitivity to separate clinical populations and neurotypical controls. This study supports the use of the SFS for those with SAD and Early Psychosis. Lower internal consistency in ASD populations suggests further research in larger samples is required and that the relationship between its scales are likely different to other populations. Alternative scales or significant other reports may be required for adults with ASD.