[Diagnostic Observation Scale for Autistic Disorders: initial results of reliability and validity].

OBJECTIVE

To examine the psychometric properties of the German version of the Autism Diagnostic Observation Schedule (ADOS).

METHODS

Interrater and retest reliability, internal consistency, convergent and diagnostic validity were determined in a total sample of 137 subjects with autism, 23 with atypical autism or pervasive developmental disorder not otherwise specified, 16 with Asperger-syndrome and 13 with other psychiatric disorders.

RESULTS

Interrater and retest reliability on the level of diagnosis (kappa w = 1.00 and .62) and raw-scores (ru = .84 and .79) were good. Likewise, the internal consistency of the algorithm scale communication and social interaction of modules 1 to 4 was fair (ru = .78 to .89). The categorical convergence for autism between the ADOS and the Autism Diagnostic Interview-Revised (ADI-R) reached 79% (kappa = .23), with their corresponding subscales correlating moderately (rtc = .31 to .45). The concordance of the ADOS judgment and the clinical consensus diagnosis was 77% (kappa w = .37), with a sensitivity of the ADOS of 90.4% and a specificity of 48.1% regarding the discrimination of autism and other autistic disorders.

CONCLUSIONS

The ADOS is a reliable and sufficiently sensitive diagnostic tool in the assessment of autistic disorders. For ICD-10/DSM-IV classification and to ensure a high specificity of diagnosis additional information concerning repetitive, stereotyped behavior and early development (e.g. taken from the ADI-R) has to be collected.