Insurance Institute for Highway Safety Tests Crash Avoidance Systems Until now consumers who bought frontal crash prevention systems - including forward collision warning and automatic braking - had to take the word of automakers that the systems did something besides pump up the price. But today the first ratings of 74 vehicles with such systems were released by the Insurance Institute for Highway Safety, a group financed by the insurance industry. The insurance institute is the first group to rate these front crash prevention systems based on real-world track testing, using a protocol similar to one developed by the European New Car Assessment Program - known as Euro N.C.A.P. - which is Europe's crash testing program. The I.I.H.S. ratings are significant because they represent an effort to go beyond typical crash test standards to evaluate systems designed to prevent crashes. "These ratings don't tell about the protection that these cars will offer in a crash, but they do tell which systems are going to help them stay out of more crashes," David Zuby, chief research officer for I.I.H.S., said in a telephone interview. In response to I.I.H.S. testing of crash avoidance systems, the National Highway Traffic Safety Administration said it is engaged in its own research into the reliability of the technology, as well as how to effect earlier implementation by manufacturers. "The agency applauds the Insurance Institute for Highway Safety's new test program that rates the performance of these systems and looks forward to seeing how vehicle manufacturers respond to these new rating criteria and the safety benefits it will yield consumers," N.H.T.S.A. said in a statement. Frontal crash avoidance systems are designed to keep a distracted driver from rear-ending the car ahead. Typically, such a system scans the road, often using radar or cameras, while a computer calculates the rate at which the distance between the equipped vehicle and the one ahead of it is closing. If the distance decreases too quickly, some systems - called autonomous or automatic braking systems - apply the brakes to either slow or completely stop a vehicle in an attempt to avoid rear-ending the car ahead. Braking configuration and rate differs by manufacturer. In other setups, called forward collision warning systems, an audible alert sounds to warn drivers if the vehicle's sensors detect the an impending crash with the vehicle in front. In general, they do not slow or stop the vehicle, although some systems come with automated braking. In its rating of vehicles with crash avoidance features, I.I.H.S. rated models as "superior," "advanced" or "basic," depending on whether they had automatic braking and how much speed the vehicles could reduce in 12- and 25-mile-per-hour tests on a track. Vehicles received a superior rating if they had autobrake and could avoid a crash or reduce speeds by 10 m.p.h. or more in both tests. To get an advanced rating, vehicles had to have autobrake and avoid a crash, or reduce speeds by 5 m.p.h. or more in one of the two tests. Vehicles with autobrake also received credit for having a forward collision warning system that met N.H.T.S.A. performance criteria. Vehicles with forward collision warning but without an autobrake system earned a basic rating. But even forward collision warning alone can help drivers avoid crashes - and warning systems are more widely available than autobrake systems, according to I.I.H.S. During testing - which was recorded in a series of videos - an engineer drove each vehicle toward a stationary target that simulated the rear of a vehicle. Sensors in the test vehicle monitored its lane position, speed, time to collision, braking and other data. In the first round of testing, I.I.H.S. tested 74 moderately-priced and luxury 2013-14 midsize cars and sport utility vehicles. Of those models, seven earned the top rating of superior, six garnered an advanced rating, 25 took away a basic rating and 36 models either did not offer a crash avoidance system or had one that didn't meet the institute's criteria. The very top-rated models to receive a superior rating were the Subaru Legacy sedan and Outback wagon. Both have a system called EyeSight, which kept the vehicles from hitting the target by reducing vehicle speed by 12 m.p.h. in the 12 m.p.h. test and by 25 m.p.h. in the 25 m.p.h. test. In contrast, the system in the Acura MDX, which received an advanced rating, reduced vehicle speed by 7 m.p.h. in the 12 m.p.h. test and by 6 m.p.h. in the 25 m.p.h. test. This technology is becoming increasingly available and consumers have questions about it. Mr. Zuby said. We see that some of it is working well, so we want to start providing important information about it as well.