Early Intervention Improves Cognitive Outcomes for Preterm Infants: Randomized Controlled Trial

Objective: The goal was to examine the effectiveness of an early intervention on cognitive and motor outcomes at corrected ages of 3 and 5 years for children with birth weights (BWs) of <2000 g.

Methods: A randomized controlled trial of a modified version of the Mother-Infant Transaction Program was performed. Outcomes were assessed with the Bayley Scales of Infant Development II and the Wechsler Preschool and Primary Scale of Intelligence-Revised at 3 and 5 years, respectively. McCarthy Scales of Children's Abilities and the grooved pegboard test were used to test motor outcomes at 5 years.

Results: A total of 146 infants were assigned randomly (intervention group: 72 infants; control group: 74 infants). The mean BWs were 1396 ± 429 g for the intervention group and 1381 ± 436 g for the control group. After adjustment for maternal education, a nonsignificant difference in Mental Developmental Index scores at 3 years of 4.5 points (95% confidence interval: -0.3 to 9.3 points) in favor of the intervention group was found, whereas the intervention effect on full-scale IQ scores at 5 years was 6.4 points (95% confidence interval: 0.6-12.2 points). Significantly more children in the intervention group had IQ scores of ≥ 85 at 3 and 5 years. There were no differences between the groups with respect to motor outcomes.

Conclusion: This modified version of the Mother-Infant Transaction Program improved cognitive outcomes at corrected age of 5 years for children with BWs of <2000 g.