The conventional wisdom suggests that drivers who text on their cell phones, e-mail, or even chat on hands-free headsets are more accident prone than undistracted drivers. This idea makes intuitive sense. But does science support it? Have studies demonstrated a clear causal link between driver cell phone use and increased road risk?
Let’s examine a few key studies.
Virginia Tech Transportation Institute study
The Virginia Tech Transportation Institute (VTTI) conducted several naturalistic studies in 2009, during which researchers documented 6,000,000 miles of driver behavior. The VTTI analyses revealed a complex picture, suggesting risk depends not just on behavior (e.g. texting vs. talking on a headset) but also on the type of vehicle driven (e.g. light vehicle vs. truck). According to a summary in Virginia Tech News, “manual manipulation of phones, such as dialing and texting… can lead to an increase in the risk of being involved in a safety critical event, such as a crash or near crash. However, talking or listening increased risk much less for light vehicles and not at all for trucks. Text messaging is associated with the highest risk of all cell phone related tasks.”
University of Utah study
A University of Utah funded study, published in the journal of the Human Factors and Ergonomics Society, suggested that cell phone distraction causes 2,600 deaths on U.S. roads every year and 330,000 injuries. According to David Strayer, a psychology professor at the University of Utah, “if you put a 20-year-old driver behind the wheel with a cell phone, their reaction times are the same as a 70-year-old driver who’s not using a cell phone… it’s like instantly aging a large number of drivers.” In 2001, Strayer and his team published data that suggested that drivers who use hands-free devices get dangerously distracted. Strayer et al. have also asserted that driving while chatting on a cell phone is equivalent to driving with a blood alcohol concentration of 0.08% — the legal limit for DUI.
University of Illinois at Urbana-Champaign study
Another study conducted by researchers at the University of Illinois bolstered the hypothesis that talking on a cell leads to dangerous behind-the-wheel behavior. The head of the study, Arthur Kramer, reported that: “with younger adults, everything got worse… both young adults and older adults tended to show deficits in performance. They made errors in detecting important changes, and they took longer to react to the changes.”
The University of Illinois, University of Utah, and Virginia Tech studies all strongly supported the conventional wisdom about cell phone driving dangers. But in January 2010, a widely-publicized analysis by the Highway Loss Data Institute revealed embarrassing news. Statewide bans on cell phone use while driving radically underperformed expectations and, surprisingly, failed to limit crashes. The lesson for public policy suggests that great care must be taken when officials try to apply scientific research to public safety problems. Although banning cell phone usage while driving makes sense, how to effectively enforce these bans and thus reduce the numbers of crashes and injuries remains to be answered.