The Autism Diagnostic Interview-Revised (ADI-R)

The Autism Diagnostic Interview-Revised (ADI-R) is a standardised, structured interview conducted by a child psychologist trained in ADI-R with a parent, caregiver or other informant who knows the person’s developmental history and current behaviour well. It gathers information relevant to an autism assessment and can be used with children or adults whose mental age is above 2 years.

ADI-R is not a questionnaire for the child and it does not directly observe the child. It provides detailed developmental-history and caregiver information that a child psychologist may consider alongside current functioning, direct observation and other relevant assessment information. It cannot establish or rule out autism on its own.

What does ADI-R explore?

The interview contains 93 items and organises information across three main domains:

• Language and communication: development and use of verbal and nonverbal communication.
• Reciprocal social interaction: social responses, relationships, shared enjoyment and interaction across development.
• Restricted, repetitive behaviours and interests: routines, focused interests, repetitive actions and related patterns.

Questions also cover early development, milestones, language acquisition, play, interests and current behaviour. The child psychologist records examples and codes responses using standard administration procedures.

Who takes part in ADI-R?

The interview is completed with a parent, caregiver or another person who can provide detailed information about early development and current behaviour. The person being assessed is not asked to complete the ADI-R interview or perform test tasks.

It can be helpful for the informant to think about early developmental milestones, communication, play, friendships, routines and changes over time. Developmental records or school information may provide useful context when available, but the child psychologist determines what information is relevant to the broader assessment.

How is ADI-R different from ADOS-2?

ADI-R and ADOS-2 provide different types of information. ADI-R is an informant interview focused on developmental history and behaviour across time. ADOS-2 is a direct, structured observation of current social communication, interaction and behaviour.

A child psychologist may select one or both instruments depending on the referral question and the information already available. Neither instrument is automatically required in every assessment, and using them together does not replace clinical judgement or consideration of other possible explanations.

Can ADI-R diagnose autism?

ADI-R algorithms provide structured scores for behaviours relevant to autism, but the scores are not a diagnosis. Australian guidance recommends that diagnostic decisions use information from multiple sources and consider the person’s characteristics, strengths, support needs, developmental history and possible alternative explanations.

ADI-R results do not guarantee an autism diagnosis, NDIS access, funding, school adjustments, treatment or service eligibility. Interpretation requires appropriate training and should remain within the broader assessment question.

What can parents expect?

The child psychologist asks detailed questions and may request examples from both early childhood and current life. There are no preferred answers. Specific examples, approximate ages and descriptions of how behaviour varies across settings can help the child psychologist understand the developmental pattern. The information is then considered with the other components of the assessment.

Learn more about Quirky Kid’s autism assessments for children, or book an initial consultation to discuss the most appropriate assessment pathway.