Do Dyslexic Children Have IQs?

Abstract

Some of the problems which arise in trying to obtain IQ figures for dyslexic children are reviewed. It is suggested that the existence of these problems adds weight to the view that the concept of 'global IQ' is of dubious validity.

Computerised screening for dyslexia in adults

“…sensory impairment, English as a second or additional language, educational experience and opportunities for learning). Underlying ability/achievement differentials. Although a discrepancy between underlying ability and attainment in literacy skills is not regarded as a diagnostic criterion in these guidelines, where such discrepancies do exist, they provide further supporting evidence (Frederickson & Reason, 1995; Howe, 1997; Miles, 1996; Siegel, 1999; Stanovich & Stanovich, 1997). …”

Gender ratio in dyslexia

“…In selecting appropriate measures of intelligence, we took into account clinical experience and research evidence specific to children with SDD (compare Miles 1996). As a result of the so-called ACID profile (weakness at the Arithmetic (A), Coding (C), Information (I), and Digit Span (D) sub-tests of the Wechsler Intelligence Scale for Children) global IQ scores of SDD children tend to be depressed (see, for instance, Miles and Ellis 1981).…”

The Role of Nonverbal IQ in Screening Batteries for Reading Deficits

“…Despite all these concerns, IQ discrepancy provides an effective means of screening out garden-variety poor readers compared with children with a reading deficit. To make the intelligence tests more valid for measuring intelligence among children with dyslexia, some recommendations in administrating the tests have been suggested and quoted by (Miles, 1996a). He emphasizes that one should attempt to find global patterns in dyslexic performance in the subtests of the intelligence tests, and use these as guidelines.…”