Performance of the Autism Spectrum Rating Scale and Social Responsiveness Scale in Identifying Autism Spectrum Disorder Among Cases of Intellectual Disability

The Autism Spectrum Rating Scale (ASRS) and the Social Responsiveness Scale (SRS) have been widely used for screening autism spectrum disorder (ASD) in the general population during epidemiological studies, but studies of individuals with intellectual disability (ID) are quite limited. Therefore, we recruited the parents/caregivers of 204 ASD cases, 71 ID cases aged 6-18 years from special education schools, and 402 typically developing (TD) children in the same age span from a community-based population to complete the ASRS and SRS. The results showed that the ID group scored significantly lower on total and subscale scores than the ASD group on both scales (P < 0.05) but higher than TD children (P < 0.05). Receiver operating characteristic analyses demonstrated a similar fair performance in discriminating ASD from ID with the ASRS (area under the curve (AUC) = 0.709, sensitivity = 77.0%, specificity = 52.1%, positive predictive value (PPV) = 82.2%) and the SRS (AUC = 0.742, sensitivity = 59.8%, specificity = 77.5%, PPV = 88.4%). The results showed that individuals with ID had clear autistic traits and discriminating ASD from ID cases was quite challenging, while assessment tools such as ASRS and SRS, help to some degree.