Learning disabilities and intelligence test results: a principal components analysis of the British Ability Scales

Two samples of children with reading difficulties--145 poor readers whose word reading was one standard deviation or more below the mean and 121 dyslexic children-were tested on the British Ability Scales. The purpose of the investigation was to examine whether they would score relatively poorly on verbal tests and relatively well on non-verbal tests along the lines suggested by Lawson & Inglis (1985). Also the question of sex differences was investigated. The BAS results tended to confirm the Lawson & Inglis finding that (1) children with learning disabilities in general have verbal deficits and show significantly higher performance on non-verbal tasks, and that (2) this tendency is more pronounced in males than in females. The results, although statistically significant, are not totally consistent either within or between samples. The discussion considers possible explanations for the findings and the possibility that different subgroups of these samples might show differential effects.