A car safety test for a common type of crash -- where the front corners of two cars collide as the drivers swerve to avoid each other -- found only three of 11 midsize luxury cars earned a passing mark.
Yet the mediocre results released by the Insurance Institute for Highway Safety (IIHS) in August don't mean new cars are any less safe. They mean that safety experts have once again raised the bar.
The IIHS, which is funded by the insurance industry, runs a variety of crash tests on new cars and rates their performance as Good, Acceptable, Marginal or Poor. Consumers consult the test results to help them choose safe vehicles. The IIHS ratings are different than the five-star ratings that the National Highway Traffic Safety Administration (NHTSA) uses to present the results of tests required by federal regulations.
But both sets of ratings are adjusted periodically to reflect the state of the art in safety expectations.
Hitting the safety reset button
Typically, cars get lower crash test ratings when the tests change. In 2009, 94 cars earned the IIHS' Top Safety Pick designation. A year later, after new tests for roof strength were added, 58 cars earned that distinction.
The NHTSA gave its highest mark -- five stars -- to 95 percent of cars it tested in 2007 on frontal-crash ratings. But a new ratings system in 2011 saw the number of five-star cars drop significantly, with 19 of 33 models tested getting four stars.
With only a few cars undergoing the IIHS' new small-overlap crash test, it's too early to tell if other cars will perform as the high-end vehicles did, or if the test will spur automakers to engineer new models to accommodate the new benchmark.
The test simulates a 25 percent overlap between cars, a type of accident that is more frequent than a direct head-on crash, says David Zuby, chief research officer at IIHS. While a frontal crash would be absorbed by the crumple zone, a front overlap crash pushes a car's wheels into the wheel well, causing serious lower-body injuries that can be deadly.
An IIHS video shows how having the front quarter of a car hit a barrier damages a dummy driver.
"Good performance is going to make it less likely that people are killed," he says of the new test and the top rating. "It's also making it less likely to have injuries to the chest, head and leg."
Safer means cheaper to insure … sometimes
Ultimately fewer injuries should translate into cheaper car insurance rates. Auto insurance companies closely monitor the frequency and cost of injury claims in a given model of car. (See "How a car gets a bad reputation.")
But insurers look at repair costs as well, says CarInsurance.com consumer analyst Penny Gusner. "Some of the safest cars on the road are among the most expensive to fix," she notes, pointing to recent data from the Highway Loss Data Institute showing collision and comprehensive claims for high-dollar machinery that reflect their lofty sticker prices.
For example, a Mercedes GL-Class sport-utility has below-average claims for injuries but well above-average costs for collision and comprehensive claims. A 40-year-old man with a clean record would pay about $1,766 a year to insure it, according to Insure.com. A similarly safe Lexus GX460 -- with average collision and comprehensive claims -- would be $1,509.
Two car makers -- Honda and Mercedes-Benz -- have already said that the new IIHS test could prompt changes that add to a vehicle's weight and cost.
According to Automotive News, Honda is concerned that alterations could affect handling, ride comfort and fuel economy. Mercedes-Benz said the test recreates an "unusually severe and correspondingly uncommon accident scenario" that put its C class at a disadvantage.
Look at all ratings, not just new ones
The IIHS now has five tests for which it issues a rating: moderate- and small-overlap crash tests, side-impact crash tests, rollover ratings and head and neck restraint evaluation. A Top Safety Pick rating requires a Good (G) rating on all of them.
While the new IIHS test is important, Zuby says, new car buyers should look at its scores for all of the tests. "If you want the safest car, go for all 'G' across the board," he says.
For a little while, at least, cars achieving that mark will become rarer.
For 2012 cars that have undergone all of the IIHS tests, the only cars with Good ratings in all tests are the Acura TL and Volvo S60. The 2012 Infiniti G had the third-best score for the front small overlap test -- "A" for Acceptable -- but had a "M" Marginal rating for the rear crash test, an area less likely to have a fatal crash than the front or front corner of a car.
Small luxury sedans from Audi, Mercedes and Lexus all scored a Poor in the small-overlap crash test. (You can see the rest of the IIHS ratings here.)