Role of assessment tests in the stability of intelligence scoring of pre-school children with uneven/delayed cognitive profile.
Well-chosen IQ tests given in preschool hold their value for at least three years in kids with developmental delays.
01Research in Context
What this study did
The team followed preschoolers with uneven or delayed development. They gave the kids three IQ tests: Bayley-II, Leiter-R, and WPPSI-R-Chinese.
Three years later they tested the children again. They wanted to know if the first scores could predict the later scores.
What they found
IQ scores stayed steady across the three-year gap. Early scores strongly predicted later scores no matter which test they used.
The pattern held for children with autism, intellectual disability, or mixed delays.
How this fits with other research
Butler et al. (2021) saw the same kind of stability with edible preferences. Monthly checks for one year showed little change, just like the IQ scores.
Valluripalli Soorya et al. (2025) widens the picture. They warn that rare genetic syndromes can break standard tests, so stability may not hold for every child.
Ford et al. (2022) seems to clash. They found stable preferences only when they used single-stimulus checks, not rank-order. The difference is age and population: Ford studied older adults with dementia, while P et al. studied preschoolers with delays. Both can be true.
Why it matters
You can trust a well-given IQ score from age three to stay useful for treatment planning. Pick a test that fits the child’s language level and culture, then re-test only when big changes are expected. This saves time and keeps goals consistent across years.
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02At a glance
03Original abstract
BACKGROUND: As part of an ongoing clinical service programme for pre-school children with developmental delay in an Asian developing country, we analysed the effect of three assessment tests, that is, Bayley Scale of Infant Development-II, Leiter International Performance Scale - Revised and Wechsler Preschool and Primary Scale of Intelligence - Revised - Chinese, on the stability of intelligence quotient (IQ) of children from pre-school through early childhood. METHODS: The participants were 313 Taiwanese pre-school children with uneven or delayed cognitive profile and they were followed through early childhood. IQ stability was explored by different tests and among children of different clinical diagnosis: 168 children with non-autistic intellectual disability, 73 children with autism spectrum disorder, 58 children with mixed receptive-expressive language disorder and 14 children of other heterogeneous diagnoses. Stability of scores was evaluated using the r-squared for Pearson's coefficients to see the correlation between initial IQ (IQ1) and follow-up IQ (IQ2). Multiple linear regressions were also applied to see whether IQ1 had predictive ability for IQ2 and test-test difference in the total 313 children and each diagnostic subgroup. RESULTS: Results revealed that mean IQ1 was 65.8 ± 15.4 while mean IQ2 was 73.2 ± 17.9 for the total 313 children. The IQs were stable across an average follow-up duration of 38.6 ± 22.1 month from pre-school into early childhood. Patterns of positive correlations between IQ1 and IQ2 were noted by all the tests (r-squared = 0.43-0.5, all P < 0.001) and in the majority of diagnostic subgroups. Multiple regressions analysis also revealed that IQ1 could predict IQ2 significantly in all the tests (all P < 0.001). DISCUSSION: After careful choice of appropriate initial test, stability of IQ in children with developmental delay was noted from pre-school through early childhood. In addition, the translated version of cognitive assessment was valid for the required context of an Asian developing country. With the current emphasis on early identification and intervention for pre-school children with developmental delay, this information bears merit in clinical practice.
Journal of intellectual disability research : JIDR, 2011 · doi:10.1111/j.1365-2788.2011.01396.x