D-KEFS trail making test as an embedded performance validity measure

Area of Science:

• Neuropsychology
• Cognitive Assessment
• Psychometrics

Background:

• The Delis-Kaplan Executive Function System (D-KEFS) Trail Making Test (TMT) is a widely used tool for assessing processing speed and executive functions.
• Its potential utility as an embedded performance validity test (PVT) warrants investigation to ensure the integrity of cognitive assessments.

Purpose of the Study:

• To evaluate the effectiveness of various multi-condition indices derived from the D-KEFS TMT as embedded PVTs.
• To identify an optimal D-KEFS TMT index and cutoff score for detecting performance invalidity across different samples.

Main Methods:

• Classification accuracy of multiple D-KEFS TMT multi-condition indices was assessed in three distinct samples.
• These included a mild traumatic brain injury (TBI) sample (n=267) with defined performance-valid and invalid subgroups, a large national normative sample (n=1713), and a mild cognitive impairment (MCI) sample (n=70).

Main Results:

• The D-KEFS TMT Conditions 1-5 summation index demonstrated a sensitivity of .31 and specificity of ≥.9.
• Acceptable classification accuracy was observed in the normative and MCI samples, with the exception of the 80-89 age group in the normative sample where failure rates exceeded 10%.

Conclusions:

• The D-KEFS TMT Conditions 1-5 summation index is supported as an embedded PVT for individuals under 80 years old.
• This index is applicable across a spectrum of cognitive conditions, from normal to mild impairment, though further validation is recommended.