In a recent test of small crossover-utility vehicles, the Insurance Institute for Highway Safety (IIHS) found that front-seat passengers may not be as well protected as drivers.

In 2012, the IIHS implemented its small front overlap crash test, which involves only 25 percent of the front of a vehicle.

This is meant to simulate a collision with the corner of another car, or a fixed object like a tree or utility pole.

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Many manufacturers were not prepared for this test—which isn't conducted by government regulators—but quickly began adapting their vehicles to perform better.

Yet the improvements made in driver-side protection haven't necessarily carried over to passenger-side protection, the IIHS found.

All seven crossovers tested received the top "good" rating for driver-side protection, but results were mixed for passenger-side protection.

2015 Toyota RAV4, IIHS small front overlap crash test

2015 Toyota RAV4, IIHS small front overlap crash test

The IIHS doesn't rate cars for front-passenger protection, but if it did, only the 2016 Hyundai Tucson would have received a "good."

The 2015 Buick Encore, 2015 Honda CR-V, and 2015 Mazda CX-5 received "acceptable" scores, while the 2014 Nissan Rogue and 2014 Subaru Forester were rated "marginal."

The The 2015 Toyota RAV4 received the lowest rating—"poor."

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Small front overlap crashes are challenging to engineers because most of the vehicle's structure is bypassed, and impacts can deform the passenger compartment, moving occupants out of alignment with airbags.

In the case of the crossover test group, improvements to vehicle structure were limited to changes that would yield better test scores.

"In the short term it was better for manufacturers to make quick fixes to driver-side structures rather than delay improvements entirely," said Becky Mueller, an IIHS senior research engineer and lead author of the passenger-side crash-test study.

2015 Toyota RAV4, IIHS small front overlap crash test

2015 Toyota RAV4, IIHS small front overlap crash test

The IIHS also subjected the CR-V and RAV4 to a moderate front overlap test, where 40 percent of a vehicle's front makes contact with an object.

Both vehicles received "good" ratings, researchers said.

MORE: 2015 Ford F-150 Aluminum-Body Pickup: Mixed IIHS Safety Scores (Aug 2015)

This is likely because many cars are engineered for right-hand driver markets, and a moderate-overlap test is often required by regulators, according to the IIHS.

In contrast, only the IIHS conducts a small front overlap test.

The organization may implement passenger-side small front overlap ratings beginning next year, and is mulling making this a requirement for its safety awards, possibly in 2018.


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