Autism assessment is available using the Autism Diagnostic Interview-Revised (ADI-R), clinical diagnostic instrument for assessing autism in children and adults. The ADI-R provides a diagnostic algorithm for autism as described in the ICS-10 and DSM-IV and is appropriate for children and adults with a cognitive age of 18 months and above.
It is a standardised, semi-structured interview for care-givers/informant that takes approximately 90-120 minutes of questions in a face to face appointment. The interview contains 93 items and focuses on behaviours in three domains:
1. Reciprocal Social Interaction
2. Communication and Language
3.Restricted and Repetitive, Stereotyped Interests and Behaviours
The instrument is research-based and has inter-rater and test-retest reliability, as well as internal validity. The instrument requires substantial training in administration and scoring and only a highly trained clinician can administer the ADI-R.