Some supplementary methods for the analysis of the Delis-Kaplan Executive Function System.

Supplementary methods for the analysis of the Delis-Kaplan Executive Function System (Delis, Kaplan, & Kramer, 2001) are made available, including (a) quantifying the number of abnormally low achievement scores exhibited by an individual and accompanying this with an estimate of the percentage of the normative population expected to exhibit at least this number of low scores; (b) estimating the overall abnormality of an individual's achievement score profile with the Mahalanobis distance index; (c) calculating a composite executive function index score for an individual and providing accompanying confidence limits; and (d) providing the percentile ranks for an individual's achievement scores and executive index score (in the latter case, confidence limits on scores are also expressed as percentile ranks). With the exception of the Mahalanobis distance index, all the methods can be obtained with the equations and tables provided in this article. However, for the convenience of clinicians and to reduce the possibility of clerical error, the methods have also been implemented in a computer program.