Psychometric Properties of a New Measure to Assess Autism Spectrum Disorder in DSM-5


An earlier version of this article served as Ms. Monaghan's MA thesis.

Correspondence concerning this article should be addressed to Frederick L. Coolidge, Department of Psychology, 1420 Austin Bluffs Pkwy., University of Colorado, Colorado Springs, CO 80918. Electronic mail may be sent to


This article presents preliminary psychometric properties of a new 45-item scale, the Coolidge Autistic Symptoms Survey (CASS), designed to differentiate between children within the autism spectrum (including Asperger's Disorder) and purportedly normal children, in anticipation of DSM-5 changes, in which a single diagnostic category is proposed: autism spectrum disorder. The final sample (N = 72) consisted of 19 children diagnosed with Asperger's Disorder, 19 children who were considered loners by their parents (without an autism diagnosis), and 34 purportedly normal children. The CASS and the 200-item, DSM-IV-TR aligned, Coolidge Personality and Neuropsychological Inventory were completed by a parent. The CASS had excellent internal scale reliability (α= .97) and test–retest (r = .91) reliability. ANOVA revealed the CASS was able to discriminate significantly among the 3 groups of children. Further research with the CASS appears warranted.