IQ is irrelevant to the definition of learning disabilities

The purpose of this article was to examine the logic and the empirical data supporting the proposition that intelligence tests are not necessary for the definition of a learning disability. Four assumptions of the use of IQ test scores in the definition of learning disabilities were examined. These assumptions were (a) IQ tests measure intelligence; (b) intelligence and achievement are independent, and the presence of a learning disability will not affect IQ scores; (c) IQ scores predict reading, and children with low IQ scores should be poor readers; and (d) reading disabled children with different IQ scores have different cognitive processes and information skills. It was argued that IQ scores measure factual knowledge, expressive language abilities, and short-term memory, among other skills, and that because children with learning disabilities have deficits in these areas, their scores may be spuriously low. It was also shown that some children with low IQ scores can be good readers, indicating that low IQ scores do not necessarily result in poor reading. Empirical evidence was presented that poor readers at a variety of IQ levels show similar reading, spelling, language, and memory deficits. On logical and empirical grounds, IQ test scores are not necessary for the definition of learning disabilities.