The Effect of Age on Driving Performance in Iran Using Driving Simulator

Nearly 16,000 people are killed in driving accidents in Iran each year. The purpose of this study was, therefore, to determine the effect of age on driving performance, using a driving simulator.

This cross‑sectional study was carried out on 16 young drivers, 16 middle‑aged drivers, and 16 elderly drivers in Tehran. Driving simulators were used to check the drivers’ performances. The main scenario was driving on a freeway at an average speed of 50 km/h, when pedestrians suddenly appeared at a distance of 40 m and the drivers had to brake immediately after noticing the pedestrian. The time interval between the emergence of the pedestrian and stepping on the brake pedal was continuously recorded as the reaction time and the amount of vehicle deviation from the center of the road as the lateral deviation of the vehicle. The drivers’ mental workload was recorded after the simulated driving test, using the verbal online subjective opinion scale.

The elderly drivers had the highest mean reaction time, 963.8 ms, and there was no significant difference between the mean reaction time for youth and middle‑aged drivers (858.3 ms vs. 860 ms). Elderly drivers showed high lateral deviation, 0.69 m, and mental workload, 6.19, whereas youth drivers had the lowest lateral deviation (0.55 m) and mental workload (3.60). MANOVA revealed a significant effect of age (Pillai’s trace, V = 0.55, P < 0.001). Univariate ANOVA showed that age significantly affected the lateral deviation (P < 0.001) and mental workload (P < 0.001), but reaction time wa not age dependent (P = 0.101). Poisson regression revealed no significant effect for age on the number of collisions (P = 0.357).

Based on the variables under study, driving performance of the elderly group was poor as compared to that of the middle‑aged and young ones. Old drivers were subjected to greater mental workload when responding to the stimulus of the driving environment.