Decline of Nonverbal Executive Functions Across the Lifespan – Distinguishing Between Outcome and Process
Date of Award
Master of Arts in Psychology
Psychological Tests, Psychology
Numerous studies have attempted to validate nonverbal fluency tests but none have examined construct validity, particularly the correlation of measures and self-reported executive functioning deficits. The current study examined this issue by correlating the results of the Five-Point Test (5PT) and the Delis Kaplan Executive Functioning System (D-KEFS) Design Fluency Test with the Barkley Deficits in Executive Functioning Scale – Short Form (BDEFS-SF) in 306 English speaking adults. Participants were volunteers from undergraduate classes and those serving jury duty in a large urban city. The mean age was 36.89 ± 18.08 with an average of 14.65 ± 2.85 years of education. The majority was female (70.3%), Caucasian (76.0%), and had a primary language of English (97.7%). Results were unable to confirm the previous literature showing adequate test-retest reliability across all scores for the 5PT and for the D-KEFS Design Fluency Test as only rotation of the 5PT (rs=.84) as having good reliability. In analyzing the scales of the BDEFS-SF, the study found only a few inconsistent meaningful correlations between the summary and strategy scores of the 5PT and scales of the BDEFS-SF. When controlling for age and education, repetitions for the 5PT and the DKEFS Design Fluency Test correlated significantly with most of the scores on the BDEFS-SF, supporting repetitions on nonverbal fluency tasks as measures of executive dysfunction. A mediation analysis was significant such that education mediated the relationship between age and number of unique designs on the 5PT, b = .086, 95% BCa CI [.035, .138], as well as for the relationship between age and strategies used on the 5PT, b = .069, 95% BCa CI [.014, .122]. In general, small insignificant correlations were found between the summary scores of the two nonverbal fluency measures and the self-report measure of executive functioning, further suggesting the link between self-report of such deficits and actual deficits is tenuous at best. These findings also indicate that higher education is neuroprotective against cognitive decline.
Krivenko, Anna, "Decline of Nonverbal Executive Functions Across the Lifespan – Distinguishing Between Outcome and Process" (2017). ETD Archive. 991.