Two studies are reported that raise additional serious questions about the use of IQ scores in the definition of dyslexia. Participants in the studies were children with reading difficulties and IQ _80. Children were categorized into 'dyslexic' and 'poor reader' groups on the basis of whether or not there was a significant discrepancy between their IQ and their reading performance. The first study was based on a sample of 161 7-8-year-old children. There was a significant positive correlation (0.351) between the IQ scores of the children and the socioeconomic status (SES) scores of the parents. Furthermore, the dyslexic children had significantly higher SES scores than the poor readers. The second study investigated the changes in IQ with age, using a total of 473 children aged 7-16 years. Two key findings emerged: first, the mean IQ scores were lower for the older children, suggesting an effective decline with age; second, the ratio of poor readers to dyslexic children increased with age. The findings suggest strongly that the measured IQ of a dyslexic child decreases with age, leading to a reclassification from dyslexic to poor reader using the discrepancy approach. Two children with equivalent reading difficulties might therefore be diagnosed differently by the IQ-attainment discrepancy criterion, with a child with lower SES or who is older being more likely to be classified as a poor reader. Therefore children with lower SES or who are older are victims of discrimination if the IQ-achievement discrepancy definition of dyslexia is used.