| Type | Diagnostic instrument — direct, semi-structured observation |
|---|---|
| Age range | From ~12 months (Toddler Module) through adulthood |
| Format | 40–60 minutes of structured play, activities, and conversation with a trained examiner |
| Who administers | Clinicians with specific ADOS-2 training (psychologists, developmental pediatricians, speech-language pathologists on diagnostic teams) |
| Output | Domain scores compared against research cutoffs, plus a comparison score describing the level of autism-related features |
What actually happens in the room
To a child, a good ADOS-2 session feels like playing with a friendly adult. Underneath, every activity is a standardized "press" — a situation designed to invite social communication so the examiner can observe how your child naturally responds:
- Toys that invite shared enjoyment — does the child show, point, share a look of delight?
- A snack or a windup toy just out of reach — how does the child request? Gesture, eye contact, words?
- Interrupted routines and playful surprises — does the child reference the examiner's reaction?
- Pretend-play props (and for older children/adults: conversation, storytelling, questions about friendships and emotions)
- Opportunities to observe repetitive behaviors, unusual interests, and sensory responses
The examiner chooses one of five modules based on age and language level — from the Toddler Module (12–30 months, few or no words) up to Module 4 (verbally fluent adolescents and adults) — so the activities always fit the person being assessed.
How scoring works — and what it can't do
Behaviors are coded on standardized items, combined into an algorithm score, and compared against cutoffs for "autism" and the broader "autism spectrum" classification, plus a comparison score from 1–10 describing how prominent autism-related features were in the session. Three honest caveats:
- It's one hour of behavior. A shy child, a sick child, or a child who masks well can look different in the room than in life. That's why the ADOS-2 is designed to be integrated with history — typically the ADI-R or a thorough clinical interview — never read alone.
- The score doesn't diagnose; the clinician does. A qualified professional can diagnose autism without an ADOS-2, and can conclude a child is not autistic despite a score above cutoff (or vice versa) when the whole picture says so.
- Masking is its known blind spot. Verbally fluent children — girls especially — can perform well through a one-hour structured session. If the ADOS-2 comes back "negative" but daily life says otherwise, say exactly that to the evaluator.
How to prepare your child: don't. Seriously — no coaching, no practicing eye contact, no "be good in there." The instrument works by observing natural behavior, and the most useful thing you can bring is your child as they actually are, plus your own concrete observations and videos for the history interview.
Around the ADOS-2
A comprehensive evaluation wraps the ADOS-2 with a developmental history (ADI-R or equivalent), cognitive and language assessment, adaptive-behavior measures (Vineland-3), and a hearing test. Ask for the written report — it unlocks services. And remember: early intervention doesn't wait for any of this.
Medical disclaimer: Educational information only. The ADOS-2 is a published instrument (Lord et al., WPS). This page cannot diagnose anyone; consult a qualified clinician.