Clinical and subclinical deficits at 8 years in a geographically defined cohort of low birthweight infants.

OBJECTIVE To determine the prevalence of subclinical deficits in cognitive and motor function in low birthweight infants. DESIGN Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Wechsler Intelligence Scale for Children (WISC), the Neale analysis of reading ability, and the Stott-Moyes-Henderson test of motor impairment (TOMI). Children attending normal schools assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS 233 matched index case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING Primary and special schools. MAIN OUTCOME MEASURES IQ score, reading age in months, and TOMI score. RESULTS Index cases when compared with controls had a lower WISC score (mean IQ difference 8.8; 95% confidence interval (CI) 6.8 to 10.7), a lower reading age (mean difference 6.5 months; 95% CI 4.0 to 9.0), and poorer motor performance as shown by the TOMI score (mean difference 1.4; 95% CI 1.1 to 1.8). Of the children attending special schools, 23/46 (50%) had a WISC score < or = 50. CONCLUSIONS Low birthweight children have significant subclinical deficits of cognitive and motor function and extra resources, especially in education, may be required to meet their needs.