Safety Evaluation of Older Drivers Based on Psychological, Physical and Driving Performance

Abstract

The safety and mobility of older drivers are challenged by several age-related changes, including sensory, motor and cognitive abilities and a decline in these aspects affect the ability to drive safely. In this study we aim to quantify the overall driving performance of a sample of older drivers using data from an assessment battery and a fixed-based driving simulator. To do so, 55 participants aged 70 years and older completed tests of an assessment battery of psychological and physical aspects as well as knowledge of road signs; In addition, a driving simulator test in which specific driving situations that are known to cause difficulties for older drivers were included. To evaluate the overall performance of each driver, all the above information was combined by using the concept of composite indicators, which combines single indicators into one index score. In recent years, there has been an increasing interest in the methodology for creating a composite indicator, in which the assignment of weights to each sub-indicator is an essential step. One of the promising weighting methods is data envelopment analysis (DEA) in which based on the data set the best possible weights are determined for each Decision Making Unit (DMU) or driver in our case. In this study, instead of using the standard DEA, Common Set of Weights in DEA (CSW-DEA) is applied for the index construction. By applying the model, index values for each driver is calculated which lies between zero and one with a value equal to one identifying a best performer, whereas a score less than one implies underperforming drivers. In addition to the overall performance of the drivers, more detailed insight can be gained from the assigned weights which can be interpreted as indications of the importance shares of the psychological, physical and driving performance.