The early identification of dyslexia
The objective of this study was to develop a screening test to identify children at risk for dyslexia at four or five years of age. A battery of tests, based on recent theoretical developments in dyslexia research, and including measures such as tests of IQ, phonological and motor skills, and reaction time, was administered to 91 children (including a small group with dyslexic parents or siblings) at the age of four and five years. Subjects were followed up at 6.6 and 7 years, and a group of dyslexic children were identified. Following analysis of differences in the performance of dyslexic and non-dyslexic subjects, a number of measures of phonological skills, fine motor skills and memory were combined to form the Screening Predictive Index (SPI). It was found that early identification of dyslexia was possible at moderate levels, however limitations in the selection of outcome groups may have reduced accuracy of prediction. In addition, slow learners were found to have performed similarly to the dyslexics on the SPI and therefore, to increase tile accuracy of prediction, a further set of tests were combined into an annex to tile SPI - the Screening Predictive Index (II). Background information was also studied. Theoretical issues concerning the early manifestations of dyslexia and the relationship of dyslexia to other forms of poor reading were examined. The findings of tile study supported the existence of deficits in phonological skills in young children with dyslexia, and also difficulties with fine motor skills. However, no clear support for any of the existing theories of dyslexia was found. Further evidence of measures that distinguish dyslexics from slow learners, such as tests of cerebellar function, may be required for the accurate early identification of dyslexia.