The influence of self-awareness of driving ability on on-road performance of persons with acquired brain injury

Abstract

Previous research has shown that cognitive deficits arising from neurological impairment can impact on driving performance. The diverse nature of cognitive, perceptual and behavioural impairments experienced by drivers with neurological impairment and the resulting impact on driving ability has been the subject of extensive research involving the use of psychometric off-road measures, road safety statistics, actual on-road driving assessments and self-report. This research has shown that some drivers can compensate for limitations in their driving skills but this is dependent upon realistic self-appraisal of driving abilities. Few studies have investigated the role of self-awareness of driving abilities on on-road driving performance in persons with neurological impairment. Aims: To investigate the relationship between self-awareness of driving related abilities in neurologically impaired drivers and on-road driving performance. Participants: Retrospective data were collated on 79 participants who were referred for Occupational Therapy driving assessment, comprising 24 with Closed Head Injury (CHI) (mean age 24.67 + 5.57 yrs), 30 with Cerebrovascular Accident (CVA) (mean age 61.00 + 9.08 yrs) and 25 with 'Other' diagnosis (mean age 50.64 + 21.14 yrs). All participants held a current driver's licence or learner's permit Results: Five predictor variables were significantly associated with the on-road driving assessment outcome including three demographic variables:- diagnosis (2(2)= 7.69, p = 0.021), time since injury/illness onset (2(2)= 6.40, p = 0.041), and mileage (2(2)= 5.84, p = 0.05); and two self-awareness variables:- reaction time (2(2)= 8.04, p = 0.018), and impulse control (2(2)= 13.47, p = 0.001). Logistic regression yielded a final best model containing two predictor variables (2(4) = 20.81, p = 0.000), including diagnosis (p = 0.02) and self-awareness of impulse control (p = 0.01). Discussion and Conclusion: Participants who over-estimated their driving abilities were more likely to fail a driving assessment or require driving rehabilitation than participants who under-estimated or accurately predicted their performance and participants with a diagnosis of CVA were more likely to fail or require driving rehabilitation than those with a CHI or 'Other' diagnosis.