Effect of fatigue on performance measured by a driving simulator in automobile drivers.

OBJECTIVE To identify risk factors of performance decrement in automobile drivers. METHODS 114 drivers (age <30 years, n=57; age > or =30 years, n=57) who stopped at a rest stop area on a freeway were recruited for the study. They filled out a questionnaire on their journey, sleep/wake patterns and performed a 30-min test on a driving simulator. The test evaluates, by computerized analysis, the lateral deviation of a virtual car from an appropriate trajectory on a virtual road. A sex/age matched control group was recruited in the community. Control subjects were studied at the same time of day as the index case driver. Controls had normal sleep wake schedule, absence of long driving and performed the same driving test. RESULTS Drivers performed significantly worse than controls on the driving test. Age and duration of driving were the main factors associated with decreased performance. CONCLUSION Our driving simulator can identify fatigue generated by driving but results must be considered in relation with age of subjects.