The assessment of children with specific reading difficulties (dyslexia) using the British Ability Scales

The use of the British Ability Scales with children having specific reading difficulties is described. Eighty-three children aged eight to 16 years were given a number of subtests from the British Ability Scales, and their performance on each subtest compared to every other subtest. The children were also divided into three age groups and developmental differences observed. Based on T scores the children scored significantly less well on Speed of Information Processing, Immediate and Delayed Visual Recall, Recall of Digits, Basic Arithmetic and Word Reading across all the age ranges, when compared to the other abilities. In general subtests involving Speed of Precessing and Short Term Memory were poor, whereas tasks involving Reasoning, Spatial Imagery and aspects of the Use of the Retrieval of Knowledge were found to be average or above average. Expected reading ages for the children based on other abilities were calculated, and it was found that the children's reading abilities were well below the expected level. Various forms of intelligence quotient were also computed and it is suggested that the four abilities recommended for use in computing an IQ in the current BAS Manual are inappropriate for the dyslexic child. The children were also divided into auditory-linguistic and visuo-spatial 'subtypes' of dyslexia, and significant differences were found between the groups on Speed of Information Processing, Recall of Digits, and Block Design Level and Power. The data are related to previous work in the area of developmental dyslexia.