The aim of this study was to examine distraction effects from the use of hand-held, portable hands-free, and integrated hands-free cell phones while driving. A total of 204 participants took part in the study and their ages ranged from 18 to 84 years. Cell phone records were used to determine when drivers used their cell phone while driving. Video data was used to determine the type of cell phone used, how long it was used for, and what subtasks were executed.
The results from this study presented clear findings that visual monitoring subtasks performed on hand-held cell phones degraded driver performance and increase risk. Further, although current hands-free interfaces allow drivers to communicate with their voice, there is a concern that they still allow, and sometimes require, hand-held cell phone subtasks. Ultimately, these types of hands-free devices may lead to additional tasks which can contribute to increases in driver distraction.
Fitch, G. M., Soccolich, S. A., Guo, F., McClafferty, J., Fang, Y., Olson, R. L., & Dingus, T. A. (2013). The impact of hand-held and hands-free cell phone use on driving performance and safety-critical event risk (No. DOT HS 811 757).