The Autism Diagnostic Observation Schedule (ADOS) is a semi-structured assessment of communication, social interaction, and play (or imaginative use of materials) for individuals suspected of having autism or other pervasive developmental disorders. The ADOS consists of four modules, each of which is appropriate for children and adults of differing developmental and language levels, ranging from nonverbal to verbally-fluent. The ADOS2 is widely considered a “gold-standard” instrument for diagnosing autism spectrum disorder.

The ADOS2 can be used to diagnose children from the age of 24 months old up to adults. There is a specific module for assessing toddlers.