Abstract
Measures of early family adversity, pre-school-age IQ, school-age IQ, and reading ability were obtained from 779 Dunedin children. The data were used to examine the role of reading ability in the relationship between intellectual performance and teacher-reported behavior problems. Results of regression analyses showed that family adversity and pre-school-age IQ predicted problem behavior during the first year at school. However, reading scores accounted for a larger proportion of the variance in the later behavior problem scores than did school-age IQ scores, and when reading ability was entered in the regression equation before IQ, then reading but not IQ significantly predicted change in problem behavior during the primary school years. The results indicated that the association between IQ scores and problem behavior was mediated by reading ability and that a measure of school-age IQ has limited usefulness for models of primary school-age problem behavior.