Abstract
Objective
This project was designed to cross-validate existing performance validity cutoffs embedded within measures of verbal fluency (FAS and animals) and develop new ones for the Emotion Word Fluency Test (EWFT), a novel measure of category fluency.
Method
The classification accuracy of the verbal fluency tests was examined in two samples (70 cognitively healthy university students and 52 clinical patients) against psychometrically defined criterion measures.
Results
A demographically adjusted T-score of ≤31 on the FAS was specific (.88–.97) to noncredible responding in both samples. Animals T ≤ 29 achieved high specificity (.90–.93) among students at .27–.38 sensitivity. A more conservative cutoff (T ≤ 27) was needed in the patient sample for a similar combination of sensitivity (.24–.45) and specificity (.87–.93). An EWFT raw score ≤5 was highly specific (.94–.97) but insensitive (.10–.18) to invalid performance. Failing multiple cutoffs improved specificity (.90–1.00) at variable sensitivity (.19–.45).
Conclusions
Results help resolve the inconsistency in previous reports, and confirm the overall utility of existing verbal fluency tests as embedded validity indicators. Multivariate models of performance validity assessment are superior to single indicators. The clinical utility and limitations of the EWFT as a novel measure are discussed.
Disclosure statement
Relevant ethical guidelines were followed throughout the project. All data collection, storage and processing were done with the approval of relevant institutional authorities regulating research involving human participants, in compliance with the 1964 Declaration of Helsinki and its subsequent amendments or comparable ethical standards. Drs. Abeare and Erdodi provide forensic consultation and medicolegal assessments, for which they receive financial compensation. This research was supported by a Collaborative Research Grant from the Faculty of Arts, Humanities, and Social Sciences at the University of Windsor.