Federal legislation of the 1960s and 1970s extending educational services to learning disabled children contained a criterion requiring a severe discrepancy between an child's ability and achievement. Following a discussion of the historical context related to this decision, research related to discrepancy is reviewed using reading disabilities or dyslexia as the prototype. Topics examined include the relationship of IQ to various factors, including underlying cognitive weaknesses; varying IQ levels; stability of diagnosis; heterogeneity of the diagnostic category; genetic and neuroimaging findings; and appropriate standards of comparison. Research on the practical application of the discrepancy model is also reviewed. In general, there is little evidence to support its continued use. Three proposed alternatives are considered, and a possible model is offered that incorporates findings from research on diagnosis and intervention.
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Meyer, M.S. The Ability–Achievement Discrepancy: Does it Contribute to an Understanding of Learning Disabilities?. Educational Psychology Review 12, 315–337 (2000). https://doi.org/10.1023/A:1009070006373
- learning disabilities
- intelligence tests
- reading diagnosis