Comparisons in Cell Phone Use Rates between Talking and Manually Manipulating the Handheld Device

Abstract

Cell phone use is among the most prevalent types of in-vehicle distractions. Studies have shown cell phones to have a negative impact on driving performance, with the magnitude of these impacts varying based on the level of engagement required for phone use, as well as the complexity of the driving environment. The development of effective policies and programs to mitigate distracted driving is contingent on an improved understanding of the nature of these relationships. To this end, this study investigates the rate of cell phone use under various settings through a statewide direct observation survey. Data were collected from 200 roadside locations throughout the State of Michigan and a random effects multinomial logit model was estimated to assess how the prevalence of cell phone use varies across drivers. While several studies have investigated the prevalence of cell phone use, this study distinguishes differences in the manner of cell phone use (i.e., talking on a handheld device versus manual manipulation of the device) across drivers while controlling for important contextual factors. The results show cell phone use is generally higher among female drivers and use rates consistently decrease with age. The prevalence of cell phone use is also shown to vary significantly depending on the manner of use. Use rates are shown to differ based on changes in the driving environment, suggesting potential risk compensation on the part of motorists. The results also show a significant correlation in use rates at the same sites over time, which is reflective of important unobserved site-specific factors.