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On the reliability and standard errors of measurement of contrast measures from the D-KEFS

Crawford, John R.; Sutherland, David and Garthwaite, Paul H. (2008). On the reliability and standard errors of measurement of contrast measures from the D-KEFS. Journal of the International Neuropsychological Society, 14(6) pp. 1069–1073.

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A formula for the reliability of difference scores was used to estimate the reliability of Delis-Kaplan Executive Function System (D-KEFS; Delis et al., 2001) contrast measures from the reliabilities and correlations of their components. In turn these reliabilities were used to calculate standard errors of measurement. The majority of contrast measures had low reliabilities: of the 51 reliability coefficients calculated in the present study, none exceeded 0.7 and hence all failed to meet any of the criteria for acceptable reliability proposed by various experts in psychological measurement. The mean reliability of the contrast scores was 0.27, the median reliability was 0.30. The standard errors of measurement were large and, in many cases, equaled or were only marginally smaller than the contrast scores' standard deviations. The results suggest that, at present, D-KEFS contrast measures should not be used in neuropsychological decision making.

Item Type: Journal Article
ISSN: 1355-6177
Keywords: executive functioning; neuropsychological assessment; difference scores; psychometrics; measurement error; quantitative methods
Academic Unit/Department: Mathematics, Computing and Technology > Mathematics and Statistics
Mathematics, Computing and Technology
Item ID: 17657
Depositing User: Colin Smith
Date Deposited: 09 Jul 2009 10:11
Last Modified: 15 Jan 2016 11:36
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