Receptive language and intellectual abilities in preterm children.

Objective: The aim of this study was to examine the association between receptive vocabulary performance and intellectual quotient (IQ) in preterm born children compared to children born at term.

Method: A total of 72 preschool-age children participated in the study. Participants were divided in four groups: EG-I, including 20 moderate to late preterm born children; EG-II, comprehending 16 extremely preterm born children; CG-I and CG-II with correspondingly 20 and 16 children born at term. EG-I and CG-I as well as EG-II and CG-II groups were matched according to gender, chronological age, and family SES. The mean age of children in each group was: EG-I and CG-I: 30.3months; EG-II and CG-II: 29.1months. The assessment information was collected using an anamnesis protocol, the Brazilian criterion of economic classification, the Peabody Picture Vocabulary Test, and the Stanford-Binet Intelligence Scale.

Results: Mean scores for receptive vocabulary were significantly lower in both preterm groups (EG-I and EG-II) than in the corresponding matched groups (CG-I and CG-II). However, no significant differences were found among the preterm groups. Moreover, high correlations between vocabulary and IQ scores were found in both preterm groups (EG-I and EG-II). In contrast, no significant correlations were found when analyses considered each group of full-term born children (CG-I and CG-II).

Conclusion: Our findings indicate that prematurity status has an impact on receptive language performance and on the pattern of relationships between receptive vocabulary and general intellectual functioning.