Overview
The Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) is a widely used, evidence-based assessment for evaluating and diagnosing autism spectrum disorder (ASD) and pervasive developmental disorders. It provides a highly accurate, standardised autism evaluation across all ages, developmental levels, and language abilities.
Explore our ADOS-2 training courses
Suitable for
Suitable for use with ages 12 months through adulthood.
Product Description
'The gold standard for diagnosis of ASD.' – Journal of Clinical Child and Adolescent Psychology
The ADOS-2 is a semi-structured, standardised, autism assessment tool that evaluates:
- Communication
- Social interaction
- Play and imagination
- Restricted and repetitive behaviours
Through a series of structured activities, the ADOS-2 elicits behaviours relevant to an ASD diagnosis. These observations support clinical decision-making, treatment planning, and educational placement.
The five ADOS-2 modules
Each ADOS-2 assessment uses one module, selected according to the individual’s chronological age and expressive language level. Administration takes 40–60 minutes.
Module overview:
- Toddler Module – Ages 12–30 months; children not yet using phrase speech consistently
- Module 1 – Ages 31 months and older who do not consistently use phrase speech
- Module 2 – for children of any age who use phrase speech but are not verbally fluent
- Module 3 – for verbally fluent children and young adolescents
- Module 4 – for verbally fluent older adolescents and adults
Each module includes interactive activities using materials provided in the ADOS-2 Kit.
Example: Module 3 activities include make-believe play, storytelling, conversation tasks, and social-emotional discussions.
The Toddler Module
- Uses engaging, loosely structured activities with motivating materials to identify early signs of ASD.
- Algorithms provide "ranges of concern" rather than cutoff scores. These ranges help form clinical impressions, but they avoid formal classification, which may not be appropriate at such a young age.
- Helps clinicians determine whether ongoing monitoring or further assessment is needed.
Key ADOS-2 features
- Updated protocols, revised algorithms, a new Comparison Score, and a Toddler Module
- Provides a highly accurate picture of current symptoms, unaffected by language
- Clear, detailed administration and coding instructions
- Consistent structure across Modules 1–3 for reliable comparison
- Comparison score (Modules 1–3) allows the user to compare a child's overall level of autism spectrum-related symptoms to that of children diagnosed with ASD who are the same age and have similar language skills
- Score also makes it easier to monitor an individual's symptoms over time
- The ADOS-2 scoring software helps the user to choose the correct algorithm, converts item codes to algorithm scores, adds up the algorithm, calculates the comparison score and quickly arrives at an ADOS-2 classification or ‘range of concern’.
Standardised administration, coding and scoring
- Each ADOS-2 module includes a protocol booklet guiding the user through administration, coding, and scoring.
- As test activities are administered, the user observes the test taker and takes notes. Immediately afterwards, the test user codes the behaviours observed and then uses the Algorithm Form for scoring.
- Algorithm scores are compared with cut-off scores (Modules 1–4) to classify:
- Autism
- Autism spectrum
- Non-spectrum
- Toddler Module algorithms provide ‘ranges of concern’ rather than cut-off scores.
The most accurate picture of current ASD symptoms
The ADOS-2 demonstrates strong predictive validity. It provides a highly accurate picture of current ASD-related symptoms, based on real-time observations. Clinical psychologists, educational psychologists, speech and language therapists, psychotherapists, amongst others, use ADOS-2 assessment results to inform diagnosis, intervention, educational placement and treatment planning. The ADOS-2 is suitable for use in hospitals, clinics, schools, and any setting supporting individuals with developmental disorders.
Qualification level required:
Level 3. Please see our Test User Qualifications page for guidance and explore our range of ADOS-2 training courses.
Administration Time
40 to 60 minutes
Language Versions
English
Publication Date
2012
