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

  • Mononita Roy University of Ottawa, The Ottawa Hospital
  • Frank Molnar University of Ottawa, The Ottawa Hospital, The Bruyere Research Institute
Keywords: Trail Making Test, Trails B, driving, fitness-todrive, cut-off

Abstract

Background

Fitness-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.

Methods

Systematic 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.

Results

Forty-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.

Conclusions

There 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.

Author Biographies

Mononita Roy, University of Ottawa, The Ottawa Hospital

Division of Geriatric Medicine, Fellow, Post Graduate Year 5

Frank Molnar, University of Ottawa, The Ottawa Hospital, The Bruyere Research Institute

Division of Geriatric Medicine, The Clinical Epidemiology Program, The Regional Geriatric Program of Eastern Ontario, 6CanDRIVE: a CIHR Institute of Aging funded New Emerging Team

Published
2013-06-17
How to Cite
Roy, M., & Molnar, F. (2013). Systematic review of the evidence for Trails B cut-off scores in assessing fitness-to-drive. Canadian Geriatrics Journal, 16(3), 120-142. https://doi.org/10.5770/cgj.16.76
Section
Systematic Reviews/Meta-analysis