Language abilities in children who were very preterm and/or very low birth weight: a meta-analysis.

OBJECTIVE: To conduct a meta-analysis to characterize differences in language ability between children born very preterm (VPT, <32 weeks' gestational age), with a very low birth weight (VLBW, <1500 g), or both and in term-born control children.

STUDY DESIGN: Electronic databases were systematically searched, and 12 studies met the inclusion criteria. Effect sizes were calculated to compare VPT/VLBW children and control children.

RESULTS: VPT/VLBW children performed between 0.38 and 0.77 SD below control subjects in the areas of expressive and receptive language overall and expressive and receptive semantics. Results for expressive and receptive grammar were equivocal. Subgroup analysis of school-aged children revealed similar results. No studies assessing phonological awareness, discourse, or pragmatics were identified.

CONCLUSIONS: Language ability is reduced in VPT/VLBW children. When considering only school-aged children, this reduction is still present, suggesting that their difficulty appears to be ongoing. Rigorous studies examining a range of language subdomains are needed to fully understand the specific nature of language difficulties in this population.