Objective The current study aimed to determine whether the Delis-Kaplan Executive Function System (D-KEFS) taps into three executive function factors (inhibition, shifting, fluency) and to assess the relationship between these factors and tests of executive-related constructs less often measured in latent variable research: reasoning, abstraction, and problem solving. Method Participants included 425 adults from the D-KEFS standardization sample (20-49 years old; 50.1% female; 70.1% White). Eight alternative measurement models were compared based on model fit, with test scores assigned a priori to three factors: inhibition (Color-Word Interference, Tower), shifting (Trail Making, Sorting, Design Fluency), and fluency (Verbal/Design Fluency). The Twenty Questions, Word Context, and Proverb Tests were predicted in separate structural models. Results The three-factor model fit the data well (CFI = 0.938; RMSEA = 0.047), although a two-factor model, with shifting and fluency merged, fit similarly well (CFI = 0.929; RMSEA = 0.048). A bifactor model fit best (CFI = 0.977; RMSEA = 0.032) and explained the most variance in shifting indicators, but rarely converged among 5,000 bootstrapped samples. When the three first-order factors simultaneously predicted the criterion variables, only shifting was uniquely predictive (p <.05; R2 = 0.246-0.408). The bifactor significantly predicted all three criterion variables (p <.001; R2 = 0.141-242). Conclusions Results supported a three-factor D-KEFS model (i.e., inhibition, shifting, and fluency), although shifting and fluency were highly related (r = 0.696). The bifactor showed superior fit, but converged less often than other models. Shifting best predicted tests of reasoning, abstraction, and problem solving. These findings support the validity of D-KEFS scores for measuring executive-related constructs and provide a framework through which clinicians can interpret D-KEFS results.
|Number of pages||14|
|Journal||Archives of Clinical Neuropsychology|
|State||Published - Jan 7 2019|
Bibliographical noteFunding Information:
None of the authors have conflicts of interests to declare, but the following general disclosures are offered for the consideration of the readers. Mauricio A. Garcia-Barrera has served in the past as a consultant for Pearson. Grant L. Iverson has received research support from test publishing companies in the past, including PAR, Inc., ImPACT Applications, Inc., and CNS Vital Signs. He acknowledges current unrestricted philanthropic support from ImPACT Applications, Inc. He receives royalties for one neuropsychological test (Wisconsin Card Sorting Test-64 Card Version).
Justin E. Karr is a Vanier Canada Graduate Scholar and he thanks the Natural Sciences and Engineering Research Council of Canada (NSERC) for their support of his graduate studies. This study was completed in partial fulfillment of the requirements for his dissertation. Data used for the analyses reported within this manuscript were provided by Pearson, Inc. (2001). Standardization data from the Delis–Kaplan Executive Function System (D-KEFS). Copyright © 2001 NCS Pearson, Inc. Used with permission. All rights reserved. San Antonio: Pearson, Inc.
© The Author(s) 2018. Published by Oxford University Press. All rights reserved.
- Executive functions
- Test construction
ASJC Scopus subject areas
- Neuropsychology and Physiological Psychology
- Clinical Psychology
- Psychiatry and Mental health