Assessment of cognition and language in the early diagnosis of autism spectrum disorder: usefulness of the Bayley Scales of infant and toddler development, third edition.
Low Bayley-III scores before 3½ predict lasting language-cognitive delays in autism, so use them to justify extra therapy hours right away.
01Research in Context
What this study did
Doctors gave the Bayley-III to the toddlers who had just been diagnosed with autism. The kids were 18–42 months old.
Four years later the same children took IQ and language tests. The team asked: do the early Bayley scores forecast later skills?
What they found
Children who scored low on the Bayley-III before 3½ still scored low at age 4. The link was strongest for language and cognition.
Only two kids moved from the low group to the average group. Low early scores were a red flag for long-term delays.
How this fits with other research
Allen et al. (2001) looked at older, brighter children and saw no link between early speech delay and later skills. The two studies seem to clash, but they tested different ages and ability ranges. Early Bayley scores matter most for toddlers who already show global delays.
Camodeca et al. (2020) pushed the window even younger. They showed that a 9-month-old’s preference for speech predicts language at 24 months. Together the papers form a timeline: speech interest at 9 m → Bayley scores 18-42 m → school-age cognition.
Amore et al. (2011) warned that norm-corrected Bayley motor scores bounce around in pre-term babies. The current study adds that raw cognitive-language scores stay stable in toddlers with ASD, so you can trust low numbers and act on them.
Why it matters
If a toddler with ASD scores under the Bayley-III mean, don’t wait and see. Intensify hours, add speech and developmental goals, and re-check every six months. The score gives you a clear, parent-friendly reason to recommend more therapy now instead of later.
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02At a glance
03Original abstract
BACKGROUND: The aim of this study was to test the usefulness of the Cognitive and Language scales Bayley-III in the early assessment of cognitive and language functions in the context of an autism spectrum disorder (ASD) diagnosis. This paper focuses on the application of the Bayley-III and studies the predictive value of the test result in children with ASD with different levels of verbal ability. METHOD: A sample of 135 children (121 boys, 14 girls) with a confirmed ASD diagnosis at age 4 years were assessed with the Bayley-III before 42 months of age (m = 36.49, s = 4.46) and later with other rating scales of different psychological and psycholinguistic functions as part of a longitudinal study [McCarthy Scales of Children's Abilities (MSCA) (n = 48, 90% boys), Kaufman Assessment Battery for Children (K-ABC) (n = 38, 87% boys) or Illinois Test of Psycholinguistic Abilities (ITPA) (n = 44, 89% boys)]. Age assessment in months: MSCA (m = 48.80, s = 3.33), K-ABC (m = 51.80, s = 7.17) and ITPA (m = 54.48, s = 3.34). RESULTS: Lower scores on the cognitive and language Bayley-III scales before 3.5 years of age predicted lower cognitive and oral language levels at 4 years of age. A significant correlation was found between the Cognitive Bayley-III Scale and the General Cognitive MSCA Scale, and with the Compound K-ABC Mental Processing. An association between the nonverbal cognitive level and oral language level acquired at 4 years of age was found. CONCLUSIONS: The Bayley-III is a useful instrument in cognitive and language assessment of ASD.
Journal of intellectual disability research : JIDR, 2016 · doi:10.1155/2011/759289