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Updated: Aug 21, 2026

Multimodal Protocol for Assessing Metacognition and Self-Regulation in Adults with Learning Difficulties
Published on: September 27, 2020
Will the real discrepant learning disability please stand up?
1Department of Social Sciences, University of Leiden, The Netherlands. broeck@fsw.leidenuniv.nl
Abstract:
Willson and Reynolds (in this issue) challenged my thesis that the regression-based discrepancy method (RDM) is not a valid tool to detect aptitude-achievement discrepancies. In this response, I show that the statistical and theoretical counterarguments of Willson and Reynolds are based on a misreading of the statistical models presented. Furthermore, I demonstrate that the regression adjustment, which is largest for lower correlations, is the direct source of the lack of validity of the RDM procedure. Nevertheless, RDM can be considered a valid method to measure an achievement component that is unrelated to intelligence.
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