Is IQ-Achievement Discrepancy Relevant in the Definition of Arithmetic Learning Disabilities?

Abstract

This study was designed to test whether the criterion based on the IQ-achievement discrepancy is useful in the definition of arithmetic learning disabilities (ALD). A sample of children with ALD, garden-variety (G-V) poor mathematics performance (i.e., the poor arithmetic performance of children of below-average intelligence is believed to be nondiscrepant, or in accordance with their lower cognitive capabilities) and normally achieving children were selected using the standard-score discrepancy method (i.e., the differences between IQ and achievement standard scores). All the groups were compared to determine whether there were differences in solving addition and subtraction word problems and in other cognitive abilities related to mathematics such as working memory. There were no significant differences between children with ALD and children with G-V poor mathematics performance in solving arithmetic word problems or on working memory tasks. The performance of both groups with arithmetic disabilities was significantly below that of normally achieving children. This means that the criterion based on the IQ-achievement discrepancy does not seem to be relevant for differentiating between children with ALD and children with G-V poor mathematics performance.