Aim: To describe and compare school performance and IQ at 11 y of age in a population of 130 children weighing less than 2000 g at birth without any major handicaps (low birthweight) and a random control sample of 131 children born at term weighing over 3000 g (normal birthweight); and to evaluate the relative strength of parental factors versus child birthweight in predicting IQ.
Methods: The mothers and teachers completed validated questionnaires addressing school performance and the child's IQ was evaluated by WISC-R, prorated. In addition, socioeconomic status was investigated using different questionnaires.
Results: According to maternal reports, twice as many low birthweight children had school problems and three times as many of these children were referred to the School Psychological Service. Mean prorated IQ was 5 points lower in the low birthweight group. No statistically significant difference was found for mean IQ between the groups with birthweights of less than 1500 g vs 1500-2000 g. In a multivariate linear regression analysis, parental factors accounted for 13% of the variance in child IQ compared with only 3% accounted for by child birthweight.
Conclusion: Low birthweight significantly increases the risk of school problems.