Brief report: excellent agreement between two brief autism scales (Checklist for Autism Spectrum Disorder and Social Responsiveness Scale) completed independently by parents and the Autism Diagnostic Interview-Revised.

Agreement between the Autism Diagnostic Interview-Revised (ADI-R) and two brief scales completed by parents was 93.1% for the Checklist for Autism Spectrum Disorder (CASD) and 89.7% for the Social Responsiveness Scale (SRS) in a sample of adolescents with suspected autism spectrum disorders. Our study is consistent with others showing that brief scales like the CASD and SRS have strong psychometric support and compare favorably with the ADI-R. The CASD and SRS are each completed and scored in 15 min, whereas the ADI-R takes over 2 h to administer and score. The CASD and SRS offer a valid and cost effective alternative to lengthy and expensive measures and, by virtue of their brevity and simplicity, could facilitate diagnosis, access to treatment, and research.