[Exclusion of receptive speech disorders with the ADOS (Autism Diagnostic Observation Schedule)]

Abstract

Objective: The purpose of our pilot study was to assess the reliability and diagnostic validity of the Autism Diagnostic Observation Schedule (ADOS). The usefulness of the schedule in the differentiation between children with autism and children with a severe specific receptive language disorder is examined.

Method: Eight boys with early infantile autism and eight age- and IQ-matched boys with a specific receptive language disorder were examined with the ADOS. The reliability of the instrument was assessed using the ratings of eight pairs of raters. The agreement between diagnostic classification based on the ADOS ICD-10 algorithm and the independent clinical psychiatric diagnosis of two experts was used as the measure of validity.

Results: The reliability of the different ADOS items proved to be good among experienced raters. Various ADOS items clearly discriminate both groups. Using the ADOS ICD-10 algorithm, the clinical diagnosis of infantile autism could be confirmed for five of the eight children in this group. None of the children with the clinical diagnosis of a receptive language disorder was identified as autistic according to the algorithm.

Conclusions: In the hands of experienced raters the ADOS is a reliable diagnostic instrument. It can support the differentiation between autism and specific receptive language disorder, but additional parent information is needed to confirm the diagnosis.