Systematic review of the evidence for Trails B cut-off scores in assessing fitness-to-drive

Abstract

BackgroundFitness-to-drive guidelines recommend employing the Trail Making B Test (a.k.a. Trails B), but do not provide guidance regarding cut-off scores. There is ongoing debate regarding the optimal cut-off score on the Trails B test.The objective of this study was to address this controversy by systematically reviewing the evidence for specific Trails B cut-off scores (e.g., cut-offs in both time to completion and number of errors) with respect to fitness-to-drive.MethodsSystematic review of all prospective cohort, retrospective cohort, case-control, correlation, and cross-sectional studies reporting the ability of the Trails B to predict driving safety that were published in English-language, peer-reviewed journals.ResultsForty-seven articles were reviewed. None of the articles justified sample sizes via formal calculations. Cut-off scores reported based on research include: 90 seconds, 133 seconds, 147 seconds, 180 seconds, and < 3 errors.ConclusionsThere is support for the previously published Trails B cut-offs of 3 minutes or 3 errors (the ‘3 or 3 rule’). Major methodological limitations of this body of research were uncovered including (1) lack of justification of sample size leaving studies open to Type II error (i.e., false negative findings), and (2) excessive focus on associations rather than clinically useful cut-off scores.

Clinical Utility of the Trail‐Making Test as a Predictor of Driving Performance in Older Adults

“…Both parts of the TMT were evaluated in terms of their ability to predict a trichotomous measure of road test performance, as suggested by previously published recommendations. 20,22 Safe versus marginal or unsafe and safe or marginal versus unsafe cutoffs were of interest, because they allowed the current authors to evaluate changes in test operating characteristics as a result of treating marginal drivers as a separate group. Logistic regression models based on TMT performance in mixed samples of patients and healthy controls showed moderate discrimination ability (AUC > 0.70) but produced predictions that were not well calibrated.…”

Depression and Cognitive Impairment in Peritoneal Dialysis: A Multicenter Cross-sectional Study

“…Executive dysfunction was defined as Trails A score more than 75 seconds and Trails B score more than 180 seconds. [29][30][31] In addition, subtests of RBANS were adopted to assess immediate memory (list learning and story memory), delayed memory (list recall, list recognition, story recall, and figure recall), visuospatial skill (figure copy), and language ability (picture naming and semantic fluency). 32 The reliability and validity of RBANS have already been established in Shanghai and Beijing populations.…”

Visual‐cognitive tools used to determine fitness‐to‐drive may reflect normal aging

“…The TMT‐B is a good example. Research appears to substantiate a threshold of 180 seconds value as indicating poor fitness‐to‐drive; however, few older individuals exceed the 180‐second threshold. Using Tombaugh's data, the lower 10th percentile for adults 60 to 64 years of age has a value of 121 seconds or greater and only slightly more than 30 per cent of participants aged 85 to 89 had TMT‐B scores greater than 180 seconds.…”