Abstract
Objective
Trail Making Test—Part B (TMTB) is a common neuropsychological instrument measuring aspects of executive functioning such as set shifting and cognitive flexibility. Typically, TMTB is discontinued if not completed within 300 seconds, limiting variability in interpretation for individuals who discontinue. This study aims to alleviate this limitation by examining whether a TMT-B Efficiency (TMT-Be) score can provide useful clinical information in a memory disorder clinic population.
Methods
TMTB was administered to 167 patients (101 females, 66 males) as part of a neuropsychological evaluation. Diagnostic groups included: Alzheimer’s Disease (AD; N = 83), Mild Cognitive Impairment (MCI; N = 58), and Normal Cognition (N = 26). Ages ranged from 65–94. Participants completed TMTB according to standardized instructions. TMT-Be scores accounted for time, number of errors, and number of incomplete moves.
Results
TMT-Be scores differed significantly across diagnostic groups (ANOVA, F (2, 164) = 44.81, p < .001). Post-hoc tests using the Bonferroni correction revealed TMT-Be scores in the AD group (M = 17.48, SD = 9.23) were significantly higher than scores of the MCI group (M = 7.91, SD = 5.68) and WNL group (M = 4.65, SD = 1.67). Significant correlations between TMT-Be score and other neuropsychological measures were also found and will be presented and discussed.
Conclusion
Results support clinical utility of TMT-Be scores for diagnostic purposes, such as differential diagnosis of normal cognition, MCI, and AD. Further research with a larger number of participants and other populations may lend further support to the clinical utility of the TMT-Be scoring method.