Studies Confirm Driver Aids Reduce Crashes

The ability of so-called electronic driver assist systems to reduce crashes in the U.S. has been confirmed by two studies from the Insurance Institute for Highway Safety.

One analysis says blind-spot detectors, which warn drivers about traffic they can’t see approaching from behind, cut the rate of crashes during lane changes by 14%. The systems also lower the injury rate for such accidents by 23%.

A second study assesses lane departure warning systems, which alert motorists who drift out of their lane without signaling an intention to do so. IIHS says cars equipped with such devices have 11% fewer sideswipes, head-on crashes or single-vehicle departures than the same models without the technology. Injury accidents involving lane changes drops 24%.

The study, which looks at vehicles built in 2009-2015 by six manufacturers, adjusts for driver gender, age and insurance risk level. When such details are ignored, the overall crash rate for cars with lane departure warning systems is 18% lower than for cars that lack them. Fatalities in equipped vehicles plunge 86%.

Similar studies in other countries report considerably greater reductions in overall crash rates. IIHS says the relatively modest results in the U.S. is because most such systems are easy to turn off, and many drivers do so because they are irritated by frequent false warnings. IIHS’s advice to carmakers: Make lane departure warning systems less annoying.