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The Bayley-4 Versus the Bayley-III in Very Preterm Children at 24 Months' Corrected Age
Elizabeth M Hurrion1,2, Sol Libesman3, Samudragupta Bora2,4,5,6
1Mater Mothers' Hospital, South Brisbane, Australia.
Insights
The new Bayley-4 developmental assessment tool yields lower scores than Bayley-III, identifying more young children with developmental delay. This impacts early intervention eligibility and research comparisons.
Area of Science:
- Pediatric developmental assessment
- Child psychology
- Developmental pediatrics
Background:
- The Bayley Scales of Infant and Toddler Development are crucial for assessing young children's development.
- Previous versions, like Bayley-III, may overestimate scores and miss cases of developmental delay.
- This study investigates the performance of the newer Bayley-4 compared to Bayley-III in a preterm cohort.
Purpose of the Study:
- To compare Bayley-4 and Bayley-III scores in very preterm infants.
- To determine if Bayley-4 identifies developmental delay at higher rates than Bayley-III.
- To evaluate the clinical implications of using Bayley-4 for early intervention eligibility.
Main Methods:
- Utilized data from the SuPreme Study, a prospective cohort of 1601 very preterm infants.
- Assessed 1034 children at 24 months corrected age using either Bayley-III or Bayley-4 (Bayley-4A&NZ).
- Compared standard scores and rates of developmental delay between the two Bayley editions.
Main Results:
- Bayley-4A&NZ standard scores were significantly lower than Bayley-III across cognitive, language, and motor domains.
- Cognitive scores more than 2 SD below the mean were observed in 12.8% of the Bayley-4A&NZ group versus 4% in the Bayley-III group.
- A 4.0-fold increased risk of moderate/severe cognitive delay was noted with Bayley-4A&NZ.
Conclusions:
- Bayley-4A&NZ demonstrates lower scores and identifies a higher proportion of children with developmental delay compared to Bayley-III.
- These findings suggest more children will qualify for early support services.
- Direct comparison of research data across different Bayley editions is not recommended; further validation of other Bayley-4 versions is needed.
Objectives:
The Bayley is widely used for developmental assessment of young children. Reports suggest that Bayley-III overestimates scores and underidentifies developmental delay. Hypothesis: Using preterm cohort data, Bayley-4 scores will be lower than Bayley-III, with higher rates of developmental delay.
Methods:
Data are from the SuPreme Study, a prospective observational cohort of 1601 very preterm infants born 2013-2020. Follow-up included assessment at 24 months corrected age using the Bayley edition in routine use at the time, Bayley-III or Bayley-4 (Bayley-4A&NZ version).
Results:
Of 1509 surviving SuPreme study participants, 96.6% were followed up. Bayley scores were obtained on a subgroup of 1034 (68.5%): 525 Bayley-III and 509 Bayley-4. Baseline characteristics and corrected age at assessment were similar. Adjusted mean difference estimates between standard scores on Bayley-4A&NZ vs Bayley-III were cognitive -10.3 (95% CI [-11.9 to -8.8]; P < .001), language -5.9 (95% CI [-7.6 to -4.1]; P < .001), motor -3.7 (95% CI [-5.2 to -2.2]; P < .001. Cognitive scores more than 2 standard deviations below the mean occurred in 12.8% of Bayley-4A&NZ group vs 4% of the Bayley-III group.
Conclusions:
Bayley-4A&NZ standard scores are lower than Bayley-III scores. Adjusted mean differences between scores are large. The findings apply across a broad range of developmental functioning. The clinical corollary is a higher proportion of children are identified with developmental delay using Bayley-4, particularly moderate/severe cognitive delay-adjusted relative risk ratio 4.0. More children will meet access criteria for early support services. Further implications are that research/audit data using different editions cannot be directly compared. Studies of other Edition-4 versions are warranted.
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