Rates of executive dysfunction in undergraduate research participants

It is infrequently recognized that healthy individuals occasionally obtain impaired scores on neuropsychological measures. This research was conducted to determine how often healthy undergraduate research participants obtain impaired scores on popular measures of executive functioning. Specifically, performance on the Delis-Kaplan Executive Function System (D-KEFS) Trail Making and Color-Word Interference subtests was investigated in a sample of 335 undergraduate research participants. Rates of impaired performance varied across subtests and ranged from 11% (Color-Word Interference Word Reading) to 3% (Trail Making Test Motor Speed). In general, individuals with greater intellectual functioning had higher scores and fewer impaired scores. Findings are consistent with a broad literature describing the psychometric properties of neuropsychological measures. Researchers should recognize that it is relatively common to observe impaired scores in healthy research participants when interpreting research and clinical data