Autism and Autistic Traits: The Clinical Validity of the SRS and the SCDC

Background: Research indicates that autism is not a discrete disorder, but the extreme end of a continuously distributed trait. The Social Responsiveness Scale (SRS) and the Social and Communication Disorders Checklist (SCDC) aim to assess trait autism.

Objectives: To compare the clinical validity of the SRS and the SCDC in the same sample.

Methods: Diagnostic (sensitivity/specificity) and convergent validity with established clinical autism scales (ADI-R, ADOS, SCQ) were determined in a sample of n = 148 participants with idiopathic autism spectrum disorders (ASD), n = 255 clinical, and n = 77 neurotypical controls.

Results: The SRS showed sensitivities of .82/.72 and specificities of .75/.84 for ASD on recommended cut-offs. Sensitivities were .90/.87 and specificities .41/.47 for the SCDC. Correlations with the ADI-R, ADOS and SCQ were higher for the SRS than for the SCDC.

Conclusions: The SCDC seems superior to the SRS when screening for unspecific social and communicative deficits including autism. The SRS appears more suitable than the SCDC in clinical settings and for specific ASD screening.