Dr. Alva O. Ferdinand was one member of a team of researchers from the University of Alabama at Birmingham (UAB) School of Public Health whose study was published in the American Journal of Public Health. She explains why their work was necessary:
"Very little is known about whether laws banning texting while driving have actually improved roadway safety. Further, given the considerable variation in the types of laws that states have passed and whom they ban from what, it was necessary to determine which types of laws are most beneficial in improving roadway safety."
Across the US, legislation varies with regard to cell phone use and driving. The first state to pass a texting ban was Washington in 2007. At present, text messaging is banned for all drivers in 44 states and Washington, DC.
Of these states, all but five have primary enforcement, meaning that law officers can stop a vehicle directly as a result of the driver texting. Secondary enforcement means that an officer must have another reason such as speeding to stop a vehicle. Of the six states without a total ban of drivers texting, four prohibit novice drivers from texting, and three ban school bus drivers.
Texting is one activity that can lead to distracted driving, where the driver's attention is diverted away from the road. Texting is incredibly prevalent within US society, with around 171.3 billion text messages being sent every month.
Around 660,000 Americans are using cell phones or other electronic devices while driving at any given moment.
Among teens, 25% have reported responding to a text message at least once every time they drive, with 20% admitting to holding multi-message conversations. Around 10% of parents admit the same.
While texting, on average a driver's eyes will be off the road for 5 seconds. When traveling at 55mph, this is enough time to cover the length of a football field blindfolded.
Distracted driving is a danger to drivers, passengers and pedestrians alike. According to the US government's Website for Distracted Driving, an estimated 3,328 people were killed and 421,000 injured in motor vehicle crashes involving a distracted driver in 2012.
For the UAB study, a longitudinal panel survey was conducted, using roadway fatality data that was collected in the Fatality Analysis Reporting System between 2000 and 2010.
The study authors report that their results indicate a reduction of 3% in traffic fatalities among all age groups in states where primary texting bans were in place. This equates to around 19 deaths being prevented per year. Primary bans that only targeted young drivers were the most effective at reducing deaths in the 15- to 21-year-old age group, with an 11% associated reduction.
Primary texting bans were not associated with significant reductions in fatalities within the 21- to 64-year-old age group, however, although this group did see a significant reduction in traffic fatalities in states that had implemented a total ban on all cell phone use without hands-free technology.
States that only had secondary texting bans had not experienced any significant reductions in traffic fatalities, according to the research.
Policies to reduce deaths
"Although texting-while-driving bans were most effective for reducing traffic-related fatalities among young individuals, handheld bans appear to be most effective for adults," says Ferdinand.
She hopes that the findings of the study could alert road safety policymakers as to which types of legislation are most effective in reducing deaths among different age groups. The results should also assist policymakers in states with secondary texting bans who wish to move toward primary enforcement.
Prof. Nir Menachemi, of the Department of Health Care Organization and Policy and co-author of the study, says that health policy researchers have a responsibility to provide high-quality evidence on the health impact of laws and policies. He hopes that "policymakers act upon our findings so that motor-vehicle deaths can be prevented."
Earlier in the year, Medical News Today reported on a study that analyzed the extent of driver distraction, using black-box telematics devices and video cameras installed in cars.