Measuring exposure to driver distraction

Researchers undertake simulator and on-road studies to quantify the degree to which distraction impacts different aspects of driving performance by examining factors such as lane keeping, reaction time, speed variability, following distance, and situational awareness. However, such findings do not inform as to whether the degree of degradation will actually compromise road safety. To this end, additional information on exposure is needed. Epidemiologists use a number of methods to measure exposure and estimate risk under real-world driving conditions. In this book chapter, the authors review the types of study designs that have been used to measure drivers' exposure to distracting activities, including the strengths and weaknesses of each of the designs.