Predicting road test performance in drivers with stroke.

OBJECTIVE. The aim of this study was to develop a brief screening battery to predict the on-road performance of drivers who had experienced a stroke. METHOD. We examined 72 people with stroke referred by community physicians to an academic rehabilitation center. The outcome variable was pass or fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor, and cognitive functioning. RESULTS. The best predictive model for failure on the road test included Trail Making Test Part A and the Snellgrove Maze Task(®). CONCLUSION. A screening battery that can be performed in less than 5 min was able to assist in the prediction of road test performance in a sample of drivers with stroke. A probability of failure calculator may be useful for clinicians in their decision to refer clients with stroke for a comprehensive driving evaluation.

Assessment of driving-related skills prediction of unsafe driving in older adults in the office setting.

OBJECTIVES: To examine the sensitivity and specificity of the Assessment of Driving-Related Skills (ADReS), a clinical tool recommended by the American Medical Association for identifying potentially unsafe older drivers that includes tests of vision, motor function, and cognition. DESIGN: Cross-sectional observation study. SETTING: Memory assessment outpatient clinic of a university hospital. PARTICIPANTS: Drivers with normal cognition (n = 47) and cognitive impairment (n = 75). MEASUREMENTS: A neurologist completed the ADReS during an office visit. Additional cognitive tests of executive, visuospatial, and visuomotor function were also performed. On a separate day, participants completed a standardized on-road test, assessed by a professional driving instructor using a global safety rating and a quantitative driving score. RESULTS: In this sample of currently active older drivers with and without cognitive impairment, measures of cognition-particularly the Trail-Making Test Part B-were more highly correlated with driving scores than other measures of function. Using recommended scoring procedures, the ADReS had a sensitivity of 0.81 for detecting impaired driving on the road test, with a specificity of 0.32 and an area under the receiver operating characteristic curve (AUC) of 0.57. A logistic regression model that incorporated computerized maze task and Mini-Mental State Examination scores improved overall classification accuracy, yielding a sensitivity of 0.61, a specificity of 0.84, and an AUC of 0.80. CONCLUSION: In its present form, the ADReS has limited utility as an office screen for individuals who should undergo formal driving assessment. Improved scoring methods and screening tests with greater diagnostic accuracy than the ADReS are needed for general office practice.

Predicting road test performance in drivers with dementia.

OBJECTIVES: To develop a cognitive and functional screening battery for the on-road performance of older drivers with dementia. DESIGN: Prospective observational study. SETTING: On-road driving evaluation clinic at an academic rehabilitation center. PARTICIPANTS: Ninety-nine older people with dementia (63% male, mean age 74.2 ± 9), referred by community physicians to an occupational therapy driving clinic. MEASUREMENTS: The outcome variable was pass or fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor, and cognitive functioning, selected for their empirical or conceptual relationship to the complex task of driving safely. RESULTS: Sixty-five (65%) participants failed the on-road driving test. The best predictive model, with an overall accuracy of up to 85% when participants were blinded, included the Eight-item Informant Interview to Differentiate Aging and Dementia, Clock Drawing Test score, and time to complete the Snellgrove Maze Test or Trail Making Test Part A. Visual and motor functioning were not associated with road test failure. CONCLUSION: A screening battery that could be performed in less than 10 minutes predicted with good accuracy failure rate for the on-road driving test in this sample of older drivers with dementia. A probability of failure calculator is provided from a logistic regression model that may be useful for clinicians in their decision to refer impaired older adults for further testing. More studies are needed in larger community-based samples, along with discussions with patients, families, and clinicians, with regard to acceptable levels of test uncertainty.