Fitness to drive a car after recovery from severe head injury.

Driving skills in relation to residual psychologic impairments were studied in a sample of patients who had survived severe head injuries several years earlier. Daytime driving was studied in an instrumented car that recorded lateral position control on a highway track and during rides in the subjects' own cars with a professional observer. In comparison with a control group matched by age and driving experience, the patients performed worse on both driving tasks. In addition, the patient group showed clear impairments on a neuropsychologic test battery, despite the long intervals since their injuries. However, the only relationships found between test performance and driving involved visuomotor ability and lateral position control. No relationship was found between neurologic status and driving skill. The results are discussed in terms of patients' compensatory potential.