Autism Diagnostic Interview Revised (ADI-R)

Autism Diagnostic Interview Revised (ADI-R)

Quick Overview

The ADI-R is used to assess individuals suspected of having autism or other autism spectrum disorders. It is useful as an aid to formal diagnosis as well as treatment and educational planning. It can be used with children and adults with a developmental age above 2 years.

We also offer comprehensive training in the ADI-R - see upcoming courses here.

Product Description

The ADI-R has proven effectiveness in differentiating autism from other developmental disorders, assessing syndrome boundaries, identifying new sub-groups and quantifying autistic symptomatology.

Composed of 93 items, the ADI-R focuses on three functional domains:

  • Language and Communication
  • Reciprocal Social Interactions
  • Restricted, Repetitive and Stereotyped Behaviours and Interests

Interview questions cover eight content areas:

  • The subject's background including family, education, previous diagnoses and medications
  • Overview of the subject's behaviour
  • Early development and development milestones
  • Language acquisition and loss of language or other skills
  • Current functioning in regard to language and communication
  • Social development and play
  • Interests and behaviours
  • Clinically relevant behaviours such as aggression, self injury and possible epileptic features.

To administer ADI-R, an experienced clinical interviewer questions a parent or caregiver who is familiar with the developmental history and current behaviour of the individual being evaluated.

Administration of the ADI-R requires use of the ADI-R Interview Protocol booklet which contains the 93 items. Following a standardised procedure, the interviewer records and codes the informant's responses in the Interview Protocol booklet.

Results are scored and interpreted using a Diagnostic Algorithm or a Current Behaviour Algorithm or both depending on the purpose of the evaluation.

The ADI-R algorithms are multi-page forms on which codings from up to 42 of the interview items are scored and systematically combined to produce the formal, interpretable results. Where the purpose of the assessment is formal diagnosis with reference to the full developmental history of the individual, one of the two age-related Diagnostic Algorithms is used. If the purpose of the assessment is for treatment planning then one of the three age-related Current Life Algorithms is used. In cases where results are to be used for both purposes then both a Diagnostic and a Current Behaviour Algorithm are completed on the basis of data from one interview.

Related Products
Authors: Michael Rutter, MD., FRS., Ann Le Couteur, M.B.B.S & Catherine Lord, PhD
Duration: 90 to 150 minutes.
Languages: English
Suitable For: Children and adults with a mental age above 2 years.
Used For: Diagnosis of autism, planning treatment and distinguishing autism from other pervasive developmental disorders.
Qualification Levels: Level 3
Glossary of terms Full specification


  • Inter-rater reliability (kappa) varies between studies and will depend partly on the range of psychopathology in the sample and partly on how well trained the raters are. Lord et al (1994) found 26 of the 35 rated behavioural items to have reliabilities of .70 or greater and none were below .60. Summated ratings in the three domains (referred to as Intraclass ratings) were .93 to .97. A study by Poustka el al ((1996) showed inter-rater reliabilities to be slightly lower in a sample with a much narrower psychopathological range (all participants having autism). 27 out of the 36 behavioural items rated in this study were greater than .70 while the others fell below .60. A third study by Chakrabarti and Frombonne (2001) found correlations between raters at the Intraclass level to range from .82 to .87 for social, non-verbal and verbal with a correlation of .59 for repetitive behaviours and 0.86 for the total ADI-R score.
  • Lord et al (1993) obtained test-retest reliability data on a sample of 20 ADI-R interviews repeated after a gap of 2 to 5 months. The second interview was conducted using a different interviewer. Reliabilities ranged from .93 to .97.


Validation studies indicate good diagnostic differentiation of the overall algorithm even in pre-school children. Furthermore the studies confirm difficulties in diagnosis in young non-verbal children with low mental ages. Diagnostic validity for children with mental ages of 2 years and above is good but there needs to be caution where mental age is below 2 years.

Available Products
Code Product Name Price Pack Qty
5580201 ADI-R Kit
1 - +
5580202 ADI-R Manual
1 - +
5580203 ADI-R Interview Booklet
5 - +
5580204 ADI-R Comprehensive Algorithm Form
10 - +
5580210 ADI-R Training Package, PAL Format (must purchase alongside the ADI-R manual 5580202)
1 - +
5580211 ADI-R Training Guidebook (for use with training DVD's)
1 - +
5580212 ADI-R Set of Interview Booklets and Comprehensive Algorithm Forms for Training
1 - +
Select all