Empirical derivation and classification of subgroups of children with learning disorders at separate age levels

This study classified subgroups of learning disabled (LD) children while considering the effects of age. Specifically, scores on the Halstead-Reitan Neuropsychological Battery (HRNB) for older children, the Wechsler Intelligence Scale for Children-Revised (WISC-R), and Wide Range Achievement Test (WRAT) were clustered for a large sample of public school LD children at the age levels 9-10, 11-12, and 13-14 years old. Like clusters were then identified and collapsed across age groups. Discriminant analyses were performed at each age level, and for like clusters across ages as a measure of predictive validity. Results of this study suggested two distinct clusters at each age level; one showing diffuse deficits which varied little with age, and the other evidencing specific neuropsychological problems which may vary with age.