M-CHAT-R Autism Screening for 24-Month-Olds
24 months — the 2-year mark — is the second age at which the American Academy of Pediatrics recommends universal autism screening for all toddlers. Completing the M-CHAT-R at this visit is recommended regardless of whether specific concerns have been raised.
- Questions
- 20
- Format
- Yes / No
- Time
- ~5 minutes
- Completed by
- Parent or caregiver
- Age range
- 16–30 months
About the M-CHAT-R
At 24 months, children should be using at least 50 words and two-word phrases, engaging in pretend play, and showing clear interest in other children. They should follow two-step instructions, point to show interest in objects and events, and demonstrate consistent name response.
The 24-month screen is important even for children who screened negative at 18 months. Development changes significantly in the intervening six months, and some autism presentations become clearer as social expectations and peer interactions increase. A second screen captures any changes since the 18-month result.
Source: Modified Checklist for Autism in Toddlers, Revised — Robins, Fein & Barton (2009)
Frequently asked questions
- Why does the AAP recommend screening at both 18 and 24 months?
- Some children who screen negative at 18 months are identified at 24 months as autism traits become more apparent with age. Others show developmental regression between these points. Two screening windows increase the likelihood of early detection, enabling earlier intervention.
- My child passed the 18-month screen — should I screen again at 24 months?
- Yes. The AAP specifically recommends a second screen at 24 months. A result from six months ago reflects a different developmental snapshot. Completing the M-CHAT-R again based on current behaviour is more accurate and is standard recommended practice.
- What happens if my child screens at risk?
- A positive screen means enough reported behaviours are present to warrant further evaluation. The recommended next step is a referral to a developmental paediatrician, paediatric psychologist, or specialist autism diagnostic service. Early referral leads to earlier access to support.
- Does a positive screen mean my child has autism?
- No. A positive screen is not a diagnosis. Many children who screen positive do not receive an autism diagnosis after full evaluation. Only a qualified clinician carrying out a comprehensive assessment can diagnose autism spectrum disorder.
- How long does the screening take?
- Most parents complete the M-CHAT-R in 3 to 5 minutes. Results and guidance are available immediately after the last question.
Free · Private · Results in under 15 minutes