Screening Tools: M-CHAT and Others

Screening tools don't make a diagnosis; they are quick, practical questionnaires that help identify which children should be referred for a more detailed assessment. In this chapter, we'll look at the most commonly used screening tools and how they should be interpreted.

M-CHAT-R/F: The Most Widely Used Screening Tool

The Modified Checklist for Autism in Toddlers, Revised with Follow-Up (M-CHAT-R/F) is the most widely used tool in the world for screening ASD risk in children 16 to 30 months old. It consists of a 20-item questionnaire completed by parents, followed by a follow-up interview that is done if the first result comes back "medium-to-high risk." This two-step structure is designed to reduce false positives (that is, a child who does not actually have ASD coming back as "at risk").

M-CHAT-R/F questions include ones that can be answered from everyday observation, such as: "Does your child make eye contact with you?", "Does your child point to an object to show you something interesting?", "Does your child look at you when their name is called?", "Does your child look in the same direction you are looking?"

Did You Know? — Interpreting the M-CHAT-R/F Result

Low risk: Routine follow-up is enough; but developmental monitoring should continue at later check-ups.

Medium risk: The follow-up interview (M-CHAT-R/F) should be done; if the risk is still high after this interview, a referral is made for a comprehensive assessment.

High risk: A direct referral to comprehensive assessment and early intervention services is recommended; the referral can be made without waiting for the follow-up interview.

Other Screening Tools

In addition to the M-CHAT-R/F, other screening tools are used for different age groups or purposes:

• Infant and Early Childhood screening measures (the ITSP/ASQ family) — as part of general developmental screening, they also assess social-communication development.
• Social Communication Questionnaire (SCQ) — a parent-completed screening tool used in older children (age 4 and up).
• Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT) — another tool used in research and clinical settings, especially in very young infants.

When Should Screening Be Done in Routine Developmental Monitoring?

International pediatric guidelines recommend routine ASD screening for all children at the 18- and 24-month check-ups; in addition, screening can be repeated at any age whenever a parent or clinician has a concern. In infants who have a sibling with ASD (see Chapter 4, sibling recurrence risk), screening should be done more often and starting earlier.

When to Seek Advice

A "low risk" screening result does not mean your child definitely does not have ASD; screening tools are not 100 percent sensitive. If you have an ongoing concern, you have the right to request a comprehensive assessment regardless of the screening result.

Chapter Summary

Screening tools are a first filter that identifies which children need a more detailed assessment; they don't make a diagnosis. In the next chapter, we'll look in detail at the gold-standard diagnostic tools that form the foundation of a comprehensive assessment — the ADOS-2, ADI-R, and Vineland-3.