The Positive and Negative Syndrome Scale for Schizophrenia Autism Severity Scale (PAUSS) in young people with autism and schizophrenia.

Abstract Introduction Schizophrenia spectrum disorders (SSD) share symptoms with autism spectrum disorders (ASD). Autistic phenotypic profiles in SSD may be associated with a poor prognosis. We aimed to assess the evidences for reliability and convergent validity of the Positive and Negative Syndrome Scale for Schizophrenia (PANSS) Autism Severity Scale (PAUSS) in a sample of young people with ASD and SSD, and to use the PAUSS to explore correlates of “autistic profiles” in the SSD sample. Materials and methods ASD (n = 33, age = 13–27 years) and SSD subjects (n = 26, age = 16–35 years) underwent PANSS, Autism Diagnostic Observation Schedule-Generic (ADOS-G), Autism Diagnostic Interview-Revised (ADI-R), and Social Responsiveness Scale (SRS) assessments. We derived PAUSS total/domain scores from the PANSS and applied these back-to-back with ADOS calibrated severity scores (CSS), ADI-R current behavior algorithm (CBA) scores, and SRS scores. Results Our results show evidence for an acceptable PAUSS score reliability and convergent validity both in the ASD and SSD samples. PAUSS total and socio-communication scores significantly correlated with ADOS Overall/Social Affect CSS, both in ASD and in SSD. SSD with higher PAUSS scores (“autistic-SSD”) showed Overall/Social Affect CSS scores positioned in between ASD and “non-autistic SSD”. The PAUSS total score was significantly associated with global functioning in SSD (adjusted R2 = 0.311). Conclusions There seems to be evidence for the reliability and validity of PAUSS scores for quantifying autism symptom severity transdiagnostically and to identify “autistic phenotypes” in adolescents/young adults with SSD.