The cognitive development of low-birthweight children.

The cognitive development of 30 preterm infants and 40 growth-retarded infants was studied in comparison with 105 control children. Half of the study group had a neurologically suspect/abnormal diagnosis at birth, while the other half was neurologically normal. IQ tests of the low-birthweight group at age 4.5-6 years showed no delay in comparison with the group that was born at term and on-weight. Piagetian tests indicated an interaction effect in which the group which was born at term, on-weight and neurologically normal scored best. In the analysis of the whole cognitive battery, the neurologically suspect/abnormal group achieved significantly worse than the neurologically normal group.