Reliability and validity of the Childhood Autism Rating Scale--Tokyo version (CARS-TV).

A Japanese translation of the Childhood Autism Rating Scale (CARS) (the Tokyo version of the CARS, CARS-TV) was used with 167 developmentally disabled children under age 16. Cronbach's coefficient alpha was .87. The interrater reliability (r) for each of the 15 scales based on 128 children ranged from .43 to .77 with an average of .62. Based on the 167 children, the total CARS-TV score demonstrated a satisfactory level of taxonomic validity (Thorndike, 1982) on DSM-III diagnostic groups. The total score discriminated infantile autism and other pervasive developmental disorders more efficiently from mental retardation without an additional diagnosis of pervasive developmental disorder than an IQ. The total score also showed a satisfactory concurrent validity on the overall rating of autism.