Associations of socioeconomic status and nurturing environment with developmental outcomes in very preterm children without sensorimotor impairment: a secondary analysis of the INTACT study

Clinical Snapshot

Key Findings

• P Value: All associations statistically significant (p<0.05 based on CI exclusion of null)

• Effect Size: Parental education: β = 1.299-2.246 DQ points per education level; Group childcare: β = 1.851-3.397 DQ points

• Primary Outcome: Developmental quotient (DQ) scores on Kyoto Scale of Psychological Development at age 3 years

• Nnt Or Sensitivity: Effect sizes represent 1.3-3.4 point improvements in DQ scores per intervention level

• Confidence Interval: Education 22-24 weeks: 0.015-4.477; Childcare 28-31 weeks: 1.613-3.620

Clinical Application

Parental education support programs feasible; childcare access depends on healthcare system resources Relevant for Australian NICU follow-up programs; aligns with early childhood intervention frameworks but childcare systems differ from Japan Very preterm infants without major sensorimotor impairments in high-resource healthcare settings

Abstract

UNLABELLED: The objective of this study is to retrospectively evaluate the associations between socioeconomic status (SES), including nurturing environment, and developmental quotients (DQ) at age 3 in children born very preterm with birth weight ≤ 1500 g. This secondary analysis used follow-up data from the Improvement of NICU Practices and Team Approach Cluster Randomized Controlled Trial. Participants born < 32 weeks' gestation without major sensorimotor impairments were stratified into three groups: 22-24, 25-27, and 28-31 weeks. Multiple linear regression evaluated the associations between prenatal SES and DQ scores of the Kyoto Scale of Psychological Development (KSPD), adjusted for sex, parity, gestational age, small for gestational age, multiple births, and facilities. Post-discharge SES variables were subsequently added to assess associations with nurturing environment. Of 2148 eligible survivors, 1978 underwent KSPD testing and 1846 caregivers completed SES questionnaires. Higher parental education was positively associated with total DQ across all groups: 22-24 weeks (β = 2.246, 95% CI 0.015-4.477), 25-27 weeks (β = 1.589, 95% CI 0.408-2.770), and 28-31 weeks (β = 1.299, 95% CI 0.315-2.282). Group childcare utilization was associated with higher total DQ: 22-24 weeks (β = 3.397, 95% CI 0.893-5.901), 25-27 weeks (β = 1.851, 95% CI 0.591-3.111), and 28-31 weeks (β = 2.617, 95% CI 1.613-3.620). These associations remained after adjustments for postnatal morbidities. CONCLUSION: Among children born very preterm without major sensorimotor impairments, parental education and group childcare utilization were independently associated with more favorable cognitive outcomes at age 3. These results suggest the importance of socioeconomic and environmental support in optimizing developmental outcomes for this vulnerable population. WHAT IS KNOWN: • Prenatal and postnatal SES are associated with developmental outcomes in both preterm and term children. In addition, daily group childcare environments influence child development in the general population. WHAT IS NEW: • Among very preterm children without major sensorimotor impairments, including those born at 22-24 weeks' gestation, parental education and group childcare utilization are independently associated with more favorable cognitive and language outcomes at age 3.

References

1. 1.Kono, Y., Kusuda, S., Nishida, T., Mori, R., Toyoshima, K., Sasaki, H., Yonemoto, N., Uchiyama, A., & Fujimura, M. (2026). Associations of socioeconomic status and nurturing environment with developmental outcomes in very preterm children without sensorimotor impairment: a secondary analysis of the INTACT study. European Journal of Pediatrics. https://doi.org/10.1542/peds.2022-057092D