Cognition and language of 2-year-old very preterm children measured using brief validated parental report...

The purpose of this study is to assess the cognitive and language skills of very preterm (VP) children using brief parental report instruments at age 2 years (corrected age), potential sex differences in children's skills, and differences between four profile groups of typical/weak cognition/language. Cognitive and language skills of 110 VP children without major neurological impairment from Finnish-speaking families were assessed using brief validated parental report instruments (cognitive scale of PARCA-R, FinCDI-SF, sentence complexity subscale of PARCA-R, CSBS-DP-ITC). Based on norms, the prevalence of weak skills (< 10th percentile) varied across cognitive and language domains between 16 and 34%. Typical development was found in 47% of the participants, while 12% showed weak skills in both domains. Weak cognition with typical language was found in 19% and typical cognition with weak language in 22% of the children. While boys and girls did not differ in raw scores, girls more frequently had weak cognition and typical language in norm-based profile groups. Furthermore, the amount of perinatal risk factors and medical complications differed in profile groups of typical/weak cognition/language.

Brief parental report instruments are useful in identifying weak cognitive and language development of VP children at age 2 years. The missing sex difference indicates that sex-specific developmental trajectories may not be applicable in VP children's population at this age. Weak skills can occur in cognition or language, highlighting the importance of separate assessment. More research is needed on the influence of background characteristics in profile groups based on cognition and language.

• Very preterm children have a high risk for cognitive and linguistic delays. • Brief parental report instruments are efficient and valid in detecting delayed development, but more knowledge is needed on their utility in preterm populations.

• Brief parental report instruments are useful in detecting delayed development among 2-year-old very preterm children. • No sex differences could be detected in cognitive or language development. Approximately 40% of very preterm children had weak skills in only either cognition or language, highlighting the importance of assessing them separately.