Analysis and comparison of auditory-cognitive and visual-manual distraction risk characteristics and their effect on driving

Distracted driving is one of the most important causes of traffic crashes, leading 162 countries to establish regulations to control distracted driving, mainly by prohibiting or limiting the use of mobile phones. At present, there is no standard for regulating cellphones or other distractions. Understanding the specific risk characteristics of common distracted driving behaviors is crucial for regulatory development. However, research has been limited in comparing the risk characteristics of common distractions. Hence, this study aims to analyze and compare the risk characteristics of several auditory-cognitive and visual-manual distractions, as well as factors specific to individual drivers. Two crash surrogate indicators, lateral position and acceleration, were categorized into three risk levels. The partial proportional odds model was used to analyze lane keeping events, and the mixed-effects logit model was used for speed control events. Model results showed that, compared with the no-distraction baseline, visual-manual distraction tasks undermined both driver lane control and speed control, while auditory-cognitive distraction had little effect on lane keeping; auditory-cognitive distractions showed less risk of max deceleration than visual-manual distractions, but showed more risk of max acceleration. Additionally, it was found that older and female drivers have a higher risk of max acceleration when distracted, and older drivers have a higher risk of lane departure when distracted. These results provide data support for the development of distracted driving regulations.