Cognitive Tests and Determining Fitness to Drive in Dementia: A Systematic Review

Abstract

Evidence has shown that although all individuals with dementia will eventually need to stop driving, most can continue to drive safely early in the disease. Fitness to drive needs to be monitored, and the use of cognitive testing to determine driver safety has been suggested. This review is the first to examine cognitive test results pertaining only to individuals with dementia. The aim was to examine the relationship between cognitive tests and driving to determine whether a cognitive assessment can be implemented as a tool to examine driver safety. A systematic review of 28 studies investigating the relationship between cognitive functioning and driving in individuals with dementia was conducted. The results of this review demonstrated a lack of consistency in the findings, with some studies showing a relationship between cognitive testing and driving performance for individuals with dementia, whereas others did not. Results relating to individual cognitive tests and measures confined to a single cognitive domain were variable and not consistently associated with driving performance. Studies consistently found that composite batteries predicted driving performance. The findings from this review support the use of composite batteries comprising multiple individual tests from different cognitive domains in predicting driving performance for individuals with dementia. Scores on individual tests or tests of a single cognitive domain did not predict driver safety. The composite batteries that researchers have examined are not clinically usable because they lack the ability to discriminate sufficiently between safe and unsafe drivers. Researchers need to develop a reliable, valid composite battery that can correctly determine driver safety in individuals with dementia.

Attention Deficit Hyperactivity Disorder (ADHD) and Other Neurocognitive Factors Contributing to Road Traffic Accidents (RTA)

“…Motor vehicle collision data may play a more important role in mild cognitive impairment and preclinical dementia, as these diagnoses become more commonplace among the elderly who continue to drive. A clinically useful evidence-based algorithm for predicting safe driving among patients with mild stages of dementia remains elusive [50,51].…”

Reliability and Validity of a Method for Assessment of Executive Functions in Drivers

“…However, a major factor that contributes to road accidents is human error, which is mostly connected to specific personality traits and cognitive disturbances. A large number of studies show that safe driving requires a good level of cognitive functioning [2][3][4][5][6]. One of the key cognitive characteristics related to driving is executive functions [7].…”

Driving and dementia: a clinical update for mental health professionals: Table 1

“…While long-term procedural memory is unlikely to be compromised in dementia, impairment in other aspects of cognitive function can make driving unsafe. Given that multiple cognitive functions are necessary for driving, it is unsurprising that composite cognitive test batteries have been found to predict driving performance with greater accuracy than tests covering only a single cognitive domain 22. Despite this, composite cognitive test batteries are still unable to provide a reliable assessment of driving safety.…”

“…Despite this, composite cognitive test batteries are still unable to provide a reliable assessment of driving safety. The predictive accuracy of composite cognitive tests can be increased by combination with other types of assessments, for example, driving simulator tests and a clinical interview 21 22…”

“…Screening tools such as the Mini-Mental State Examination (MMSE) and Montreal Cognitive Examination (MoCA)23 do not correlate well with driving ability and should not be used to predict driving risk 22 24. While low scores do not necessarily indicate high risk, and high scores do not reliably predict safe driving, they may be useful as part of a more detailed clinical assessment process.…”