Drivers under 20 were especially likely to be distracted by tuning the radio or changing CDs, while young adults (ages 20 – 29) seemed to be more distracted by other passengers. Drivers over 65 were more distracted by objects or events happening outside the vehicle. Most of the distracted drivers were male (63 percent), in part because as a group males drive more than females and are more likely to be involved in serious crashes.
Approximately one-third of subjects used a cell phone while driving. Forty percent engaged in reading or writing.
Child passengers were about four times, and infants about eight times, more likely to cause distraction than adult passengers.
University of North Carolina Highway Safety Research Center Study