Patterns of performance on subtests of the Wechsler Intelligence Scale for Children-Revised are often used to identify children with learning disabilities. In a study by researchers at the University of British Columbia, performance data from 121 children with average achievement was compared with data from 143 children with reading disabilities and 100 children with specific arithmetic disability. Test results of these children, aged 6 to 16, indicate the reading-disabled and arithmetic-disabled groups had significantly lower scores than the average students on all the verbal IQ subtests. This reflects their difficulties with various aspects of information processing.
Many children with disabilities also showed a significant difference between verbal and performance IQ scores, but so did many of the average-achieving students. Although there were some children with learning disabilities who showed predicted patterns, typically 65 percent or more of the children with learning disabilities did not. And a proportion of average students showed discrepancy patterns as well. These results indicate that the patterns of performance on intelligence tests are not reliable enough for diagnosis of learning disabilities in individual children. These researchers suggest that it might be better to base diagnosis of a child’s learning disabilities on patterns of achievement test scores.
“Cognitive Functioning as Measured by the WISC-R: Do Children with Learning Disabilities Have Distinctive Patterns of Performance?” Journal of Learning Disabilities, Volume 36, Number 1, January/February 2003, pp. 48-58.
Published in ERN March 2003 Volume 16 Number 3