CLINICAL AND SUBCLINICAL DEFICITS AT 8 YEARS IN A GEOGRAPHICALLY DEFINED COHORT OF LOW-BIRTH-WEIGHT INFANTS

Objective - To determine the prevalence of subclinical deficits in cognitive and motor function in low birthweight infants. Design - Children of birth weight less than or equal to 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 less than or equal to 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.