Defining the problem: Casting a wide net over driver distraction
Oct 1, 2009 1:52 PM
Indeed, there are plenty of old-school distractions—eating, drinking, grooming, talking to a passenger, dealing with children -- as well as cell phone use and texting. Making those illegal is even harder than proposing legislation on the design and use of electronic devices. But several presentations today made it clear that there is a difference in the risk profile of “old-school” and “new-school” distraction.
First off, scientifically, there are different kinds of distractions.
- Visual distractions take your eyes off the road.
- Manual distractions take your hands off the wheel.
- Cognitive distractions take your mind off the road.
Simple in-vehicle tasks like tuning a radio (assuming you’re not navigating a complex in-car multidirectional controller) have little cognitive load, a slight visual load (a quick glance), and a brief manual load. Adjusting the radio is often accepted as a baseline for comparing the amount of distraction of other controls. Various other “old-school” distractions each register differently with respect to these demands.
But texting is a “perfect storm.” It requires you to look at the keyboard, manually manipulate the keys, and think about what you’re writing. This means texting is a visual, manual, and cognitive distraction all in one.
Beyond the science, there is naturalistic study data that show the relative risks of these behaviors. Data from Virginia Tech shows that texting increases your odds 23.2 times of having a crash. That’s off the charts compared to drinking (even odds), eating (1.6 times), or applying make-up (3.1 times.) Some distractions, like talking to a passenger or adjusting the radio, actually improved safety and had a protective effect, possibly by combating fatigue or having the passenger serving as a collision warning device.
One particular “old-school” distraction was more dangerous than the others. Reaching for a moving object increased the odds of a crash by 8.8 times. It might make a mess, but it’s safer to let your bag fly off the front seat and hit the floor than to grab for it. (It’s even safer to leave it in the trunk.)
I was curious about GPS device use, a sentiment echoed by some people who comment on our blog. The body of evidence on GPS use is much smaller than that for phones. The predominant conclusion from that data is that manually entering a destination while driving is a very bad idea. Many vehicle manufacturers lockout such functions while the car is moving. This angers some owners (“I paid for this device and now you’re not letting me use it”), especially when a passenger is also prohibited from using the navigation system. On the other hand, when you compare GPS directions to reading and handling a paper map, there is a safety gain, especially if the directions are spoken or in distilled pictograph next-turn form.
Finally, who does distracted driving effect? It’s not just vehicle drivers and passengers. Pedestrian and bicycle advocates rightly pointed out that this increases the risk to those users as well.
Next from the Distracted Driving Summit: The hands-free debate.