Objective: To evaluate the persistence of effects on health and development at age 5 years of the Infant Health and Development Program, an early childhood intervention that was provided to low-birth-weight (LBW) premature infants from neonatal discharge through age 3 years.
Design: Randomized, controlled, multicenter trial, stratified by two LBW groups: lighter (< or = 2000 g) and heavier (2001 to 2500 g).
Setting: Eight socioeconomically heterogeneous clinical sites.
Participants: Of 985 eligible infants weighing 2500 g or less and at 37 weeks' or less gestational age, 377 infants were randomly assigned to the intervention group and 608 to the follow-up only group. About two thirds of the infants in each group were in the lighter LBW stratum, and one third were in the heavier LBW stratum.
Intervention: The intervention group received home visits (from neonatal discharge through age 3 years) as well as center-based schooling (from 1 to 3 years of age). Children in both groups received pediatric surveillance.
Main outcome measures: Cognitive development, behavioral competence, and health status.
Results: At age 5 years, the intervention group had full-scale IQ scores similar to children in the follow-up only group. However, in the heavier LBW stratum, children in the intervention group had higher full-scale IQ scores (3.7 points higher; P = .03) and higher verbal IQ scores (4.2 points higher; P = .02). No significant differences between intervention and follow-up only groups in cognitive measures at age 5 years were noted in the lighter LBW infants. The intervention and follow-up groups were similar in behavior and health measures regardless of LBW stratum.
Conclusion: The early childhood intervention provided in the first 3 years of life had effects on heavier LBW premature infants' IQ and verbal performance at age 5 years that were not observed for lighter LBW premature infants. The intervention did not affect health or behavior at age 5 years in either LBW stratum.