CAST Autism Screening for 4-Year-Olds
Age 4 is the lower boundary of the CAST's validated range and a meaningful transition point as children move from nursery into more structured school environments. The CAST identifies autism spectrum traits across social interaction, communication, imagination, and repetitive behaviour.
- Questions
- 31
- Format
- Yes / No
- Time
- ~8 minutes
- Completed by
- Parent or caregiver
- Age range
- 4–11 years
About the CAST
At 4 years, children are expected to engage in collaborative pretend play, initiate and maintain social interactions with peers, follow complex verbal instructions, and show imagination in play. They are beginning to understand social rules and take turns in structured activities.
Children who show differences at 4 often present with challenges navigating group play, difficulty transitioning between activities, preference for specific routines or topics, or differences in how they use and understand social language. The CAST at this age provides a structured way to assess these traits systematically before or shortly after school entry.
Source: Childhood Autism Spectrum Test — Baron-Cohen et al., Autism Research Centre, Cambridge
Frequently asked questions
- My child is starting school soon — is this a good time to use the CAST?
- Yes. School entry is often when autism traits become more visible because of increased social demands, structured peer interaction, and behavioural expectations. Completing the CAST before or around this time means any concerns can be raised with the school SENCO or paediatrician at the start, enabling earlier support.
- Is CAST more appropriate than Q-CHAT for my 4-year-old?
- Both instruments are appropriate at age 4, which sits at the boundary. The Q-CHAT is designed for 2–4 year olds with a focus on early developmental behaviours; the CAST is designed for 4–11 year olds and captures more school-context-relevant traits. If your child is firmly 4 and either in school or about to start, the CAST is a reasonable choice.
- What happens if my child screens at risk?
- A positive CAST result means enough traits are present to warrant professional follow-up. The recommended next step is a referral to a paediatric psychologist, developmental paediatrician, or specialist autism assessment service. Bringing printed results to your GP or school SENCO can support the referral conversation.
- Does a positive screen mean my child has autism?
- No. A positive screen is not a diagnosis. Many children who score above the CAST threshold do not receive an autism diagnosis after full evaluation. Only a qualified clinician conducting a comprehensive developmental assessment can diagnose autism spectrum disorder.
- How long does the CAST take?
- Most parents complete the 31 CAST items in 8 to 10 minutes. Your result with a score band and guidance is available immediately after the last question.
Free · Private · Results in under 15 minutes