A MODEL FOR STUDIES OF READING-DISABILITY

Current definitions of reading disability and/or dyslexia all involve the assessment of a discrepancy between reading ability and measured intelligence. These discrepancy definitions carry the implicit assumption that the reading difficulties of the dyslexic stem from problems different from those characterizing the poor reader without IQ discrepancy. The phonological-core variable-difference model is a framework for interpreting the evidence on the cognitive differentiability of poor readers of different types. The model and empirical data pertinent to it are discussed. Scientific and educational classification procedures that follow from the model are described. Problems with the use of intelligence test scores as aptitude benchmarks in the measurement of discrepancy are discussed. Finally, it is argued that procedures of discrepancy assessment, including those proposed here, are threatened by findings that the acquisition of literacy fosters the very cognitive skills assessed by aptitude measures. © 1993 Academic Press. All rights reserved.