Driving and cognitive function in people with stroke and healthy age-matched controls

ABSTRACT

The decision to return to driving is both complex and difficult. It is often made with clinician support, perhaps on the basis of results from standardized paper and pencil tests, and less frequently an assessment of on-road driving. However, the resources required and inherent reliability and validity challenges suggest that greater use of computerization and driving simulation may play a useful role in the assessment process. In this study, thirty-six age-matched healthy and post-stroke drivers completed standard psychometric assessments (including NART, MMSE, BADS, IADL), computer delivered cognitive assessments (including SART, N-Back, Simple Reaction Time), as well as simulated and on-road assessments of driving. While significantly different in terms of psychometric and computer-based assessments, the healthy and post-stroke drivers who completed the on-road test did not differ. In contrast, driving in the portable simulator showed impaired driving, on some but not all driving manoeuvres, for those who failed the on-road test or had voluntarily ceased to drive. These results are discussed in terms of the implications they have for the multi-faceted nature of driving as a skill, and the need to involve simulation when assessing fitness to drive.

KEYWORDS:

• Stroke
• driving assessment
• executive function
• driving simulator

Acknowledgements

The authors wish to acknowledge the support of Ireland’s Road Safety Authority under “Fitness to Drive following Neurological Disorder: Integrating Off-Road, Simulator and On-Road Driver Performance”, as well as the technical assistance at various stages of the overall project by Dr Amanda Stephens, Dr Steve Trawley and Dr Chris Burns. Particular thanks are due to Barbara Howe, who collected all of the data reported here, but regrettably left the project before reporting. We acknowledge also the very generous contributions of Professors Robyn Tate and Barbara Wilson when comment on earlier drafts of this manuscript. Finally, the first author wished to dedicate this paper to Stephen Brooksbank, a passionate driver and sometime father-in-law, who suffered a fatal ischemic attack as this manuscript was being revised.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 Errors with respect to: Rules/Checks, Positioning, Observation, Reaction to Hazards, Mirrors, Clearance /Overtaking of objects, Signalling, Alighting, Making Progress, Vehicle Controls, Speed, Traffic Controls, Right of Way, Reversing, Turning about in road, Parking; Driving faults were recorded in categories according to these manoeuvre/traffic circumstances, the nature of the error and its seriousness (see Road Safety Authority, 2009). Faults are regarded as: Grade 1 fault:- Minor fault (i.e. a mistake which does not cause immediate danger, e.g. driving in incorrect gear), Grade 2 fault:- More serious fault (combination of minor faults in same aspect of driving or potentially dangerous error), Grade 3 fault:- Dangerous/ Potentially Dangerous fault (i.e. immediate danger to self or others), or total disregard of traffic controls. Failure of the test arises when an applicant incurs any of the following: 1 or more grade 3 faults, 4 of the same grade 2 faults for a single aspect, 6 or more grade 2 faults under the same category, 9 or more grade 2 faults overall. Grade 1 faults do not affect the test result. Although not officially a fault category in RSA scheme, our assessor recorded a further level of fault, where his action was required to make the situation safe. This occurred only on a single occasion in all drives but is included for completeness in Figure 5, but is otherwise regarded as a Grade 3 fault.

Additional information

Funding

This work was supported by Road Safety Authority (Ireland).