Revisiting Discrepancy Theory in Learning Disabilities: What Went Wrong and Why We Should Go Back

Are WISC IQ scores in children with mathematical learning disabilities underestimated? The influence of a specialized intervention on test performance

BACKGROUND

Intelligence measures play a pivotal role in the diagnosis of mathematical learning disabilities (MLD). Probably as a result of math-related material in IQ tests, children with MLD often display reduced IQ scores. However, it remains unclear whether the effects of math remediation extend to IQ scores.

AIMS

The present study investigated the impact of a special remediation program compared to a control group receiving private tutoring (PT) on the WISC IQ scores of children with MLD.

METHODS

We included N=45 MLD children (7-12 years) in a study with a pre- and post-test control group design. Children received remediation for two years on average.

RESULTS

The analyses revealed significantly greater improvements in the experimental group on the Full-Scale IQ, and the Verbal Comprehension, Perceptual Reasoning, and Working Memory indices, but not Processing Speed, compared to the PT group. Children in the experimental group showed an average WISC IQ gain of more than ten points.

CONCLUSION

Results indicate that the WISC IQ scores of MLD children might be underestimated and that an effective math intervention can improve WISC IQ test performance. Taking limitations into account, we discuss the use of IQ measures more generally for defining MLD in research and practice.

Prevalence of LD From Parental and Professional Perspectives: A Comparison of the Data From the National Survey of Children's Health and the Office of Special Education Programs' Reports to Congress

Since the emergence of the field of learning disabilities (LD) in the late 1960s and early 1970s, controversy has surrounded issues regarding methods used for identification. The prevalence of students identified as LD increased steadily from the 1970s until the beginning of the 21st century, at which time it has decreased until at least 2011 (the most current data available from the U.S. Office of Education). In this article, I compare the prevalence rates of children aged 6 to 17 years being served in schools according to the Office of Special Education Programs with the prevalence rates as reported by parents on the National Survey of Children's Health. To date, no such comparison has been made that takes into account parents' knowledge of their children's disabilities. Results of the analyses reveal that parents report that their children have LD at a significantly higher rate than what is reported by schools of students receiving LD services. Most important, the longitudinal trend from 2001 to 2011 indicates that parents are reporting a slight increase whereas the Office of Special Education Programs is reporting a dramatic decrease in LD.