Acceptability and concurrent validity of measures to predict older driver involvement in motor vehicle crashes: an Emergency Department pilot case-control study

Abstract

Introduction: Older drivers have one of the highest motor vehicle crash (MVC) rates per kilometer driven, largely due to the functional effects of the accumulation, and progression of age-associated medical conditions that eventually impact on fitness-to-drive. Consequently, physicians in many jurisdictions are legally mandated to report to licensing authorities patients who are judged to be medically at risk for MVCs. Unfortunately, physicians lack evidence-based tools to assess the fitness-to-drive of their older patients. This paper reports on a pilot study that examines the acceptability and association with MVC of components of a comprehensive clinical assessment battery.

Objectives: To evaluate the acceptability to participants of components of a comprehensive assessment battery, and to explore potential predictors of MVC that can be employed in front-line clinical settings.

Methods: Case-control study of 10 older drivers presenting to a tertiary care hospital emergency department after involvement in an MVC and 20 age-matched controls.

Results: The measures tested were generally found to be acceptable to participants. Positive associations (p</=0.05) with past or current MVCs were found for components of the MMSE (e.g. orientation to time, spelling WORLD backwards), components of the Driving Habits Questionnaire, components of the Ottawa Driving and Dementia Toolkit questions for patients, the response that participants were "bothered a great deal by Diabetes Mellitus", and the Timed Toe Tap Test.

Conclusions: Based on their degree of acceptability to patients and their positive associations with MVC, the MMSE, the Driving Habits Questionnaire, the Ottawa Driving and Dementia Toolkit patient questions merit further study regarding their ability to identify older drivers at high risk of future motor vehicle crashes. Given the paucity of physical examination measures that are theoretically linked to fitness-to-drive, the new physical examination tests introduced in this paper (e.g. the Timed Toe Tap Test, the Peripheral Vision Finger Test, the Neck Rotation Finger Test, and the Coin-catch Reaction Time Test) represent additions to this field of research and also merit consideration for further study.