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ASK PINNACLE · QUESTIONS, EXPLANATIONS & NEXT STEPS

Cdi

Explore explanations, everyday questions and next steps connected with cdi.

5 published answers · English

Understanding

Answer

At What Age Is the CDI Used for a Child?

The MacArthur–Bates Communicative Development Inventories (CDI) are parent-completed questionnaires used to understand early communication in young children, typically from around 8 to 30 months. The Words and Gestures form suits infants of about 8–18 months, while the Words and Sentences form suits toddlers of about 16–30 months. It is a helpful snapshot of vocabulary, gestures and early sentences — a starting point for support, not a diagnosis.

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What is the MacArthur–Bates Communicative Development Inventories (CDI)?

The MacArthur–Bates Communicative Development Inventories (CDI) are parent-report questionnaires that measure a young child's early communication — typically from around 8 months to 3 years. Because parents complete them from everyday life, they capture real-world skills: words understood, words said, gestures, and early word combinations. The CDI is a screening and research tool, not a diagnosis; a low score is an invitation to look more closely with a professional.

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Assessment & diagnosis

Answer

How does the CDI compare with the AbilityScore developmental assessment?

The CDI is a parent-reported checklist that gives a validated snapshot of early vocabulary and communication, while the AbilityScore® is a clinician-administered structured assessment of the whole child across many developmental domains. They are complementary, not competing — a CDI can flag a concern, and an AbilityScore® builds the fuller picture that guides a personalised plan. Only a qualified Pinnacle clinician can confirm what any result means.

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Should My Child Have a CDI Assessment?

The MacArthur–Bates CDI is a parent-completed checklist of the words, gestures and early sentences your child understands and uses, usually for ages 8–30 months. It is gentle, non-invasive and based on what you see at home, taking 20–40 minutes. Whether your child should have one depends on your concerns and age — a Pinnacle clinician can confirm if it's the right fit and combines it with a clinician-administered assessment, never a label.

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When the CDI Is Indicated: Strengths and Limits in Early Childhood

The MacArthur–Bates CDI is indicated as a norm-referenced parent-report screen of early communication — gestures, comprehension, expressive vocabulary and emerging grammar — across roughly 8–37 months. It is strong for quick, ecologically valid measurement of expressive lexicon and flagging late talkers, but limited by informant reliability, weaker receptive coverage, and its status as a screen rather than a diagnostic test. At Pinnacle it sits alongside the clinician-administered AbilityScore® and direct sampling.

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