The IIHS ratings are influential because many auto shoppers find them while researching vehicles on the Internet. The group says its crash tests and ratings are designed to get automakers to improve the crashworthiness of their vehicles.
The ratings are for the institute's "small overlap" crash test that covers only 25 percent of a vehicle's front end. The test was added to the IIHS evaluations last year, with the institute aiming to push automakers into bolstering the crash resistance of their vehicles.
The group's tests are more stringent than the U.S. government's full-width front crash test. The institute says that in many vehicles, a crash affecting one-quarter of the front end misses the main structures designed to absorb the impact of a crash. Yet such crashes account for nearly a quarter of the collisions that cause serious or fatal injuries to people in the front seats, IIHS said.
The new Ford Escape, the top-selling small SUV so far this year, got a "poor" overall rating, while Honda's CR-V, the No. 2 seller, got a "marginal" rating. Toyota's RAV-4, another big seller, hasn't done the testing yet because Toyota asked for a delay to improve the vehicle's structure, the IIHS said.
Other SUVs getting "poor" ratings were the Jeep Patriot, Buick Encore, Kia Sportage and Hyundai Tuscson, the institute said. The BMW X1, Nissan Rogue, Mazda CX-5, Volkswagen Tiguan and Jeep Wrangler two-door all got "marginal" ratings.
Ford said in a statement that the Escape is safe because it is equipped with advanced safety features and a structure designed to manage the impact of a crash. But the company said it takes new developments in crash performance seriously.
The Forester and Outlander Sport each received the IIHS' coveted "Top Safety Pick Plus" award because they performed well in multiple tests including the small offset crash. Many of the other SUVs, including the Escape and CR-V, won "Top Safety Pick" designations, but didn't get the "plus" due to their performance in the small offset tests. Only 20 vehicles across all car segments have received the IIHS "Top Safety Pick Plus" award.
"With the redesigned Forester, Subaru's engineers set out to do well in our new test, and they succeeded," Joe Nolan, the institute's vice president of vehicle research, said in a statement. "This is exactly how we hoped manufacturers would respond to improve protection."
All SUVs tested, except the Forester, were 2012 or 2013 models. The institute said tests of 2012 models were valid because no significant design changes were made between model years.
Honda said in a statement that the CR-V earned a Top Safety Pick award, which was the best when it was introduced in 2011. The company would not comment when asked if it's reworking the CR-V so it does better in the small offset test.
Chrysler said the Wrangler and Patriot both meet or exceed all government safety requirements and perform well in real-world driving. Like most of the vehicles tested, both were designed before the IIHS added the small offset test.
The IIHS tests have a big impact on car-buying decisions because people are concerned about safety when they shift to smaller vehicles, said Jeff Schuster, senior vice president of auto sales forecasting for LMC Automotive, an industry consulting firm. People buy the small SUVs, which also are called crossovers, or CUVs, because they perceive them to be safer than cars, he said.
The test results "could impact sales of these models, but more so with families and with parents purchasing these for their kids," he said in an email.
IIHS conducts its small offset test by crashing vehicles into a fixed 5-foot-tall barrier at 40 mph to simulate collisions with a utility pole or tree. The institute gives vehicles demerits when the structure intrudes into the passenger compartment, or if a crash dummy suffers injuries to head, neck, chest or other parts of the body. The group also measures how well seat belts and air bags protect people. "Good" is the top rating, followed by "acceptable," then "marginal" and "poor."
IIHS is a nonprofit research group funded by auto insurance companies.
How models fared
Safety officials crashed the SUVs into a 5-foot-tall barrier at 40 mph and measured how they held up, how the air bags and seat belts worked, and the potential for injuries to the head, neck, torso and other parts of the body.
Subaru Forester • Good
Mitsubishi Outlander Sport • Acceptable
BMW X1 • Marginal
Nissan Rogue • Marginal
Mazda CX-5 • Marginal
Honda CR-V • Marginal
Jeep Wrangler • Marginal
Volkswagen Tiguan • Marginal
Hyundai Tucson • Poor
Kia Sportage • Poor
Buick Encore • Poor
Jeep Patriot • Poor
Ford Escape • Poor