Small pickups fared poorly in a crash test designed to assess rear-seat passenger safety.

The Insurance Institute for Highway Safety test examined the crew cab versions of the Chevrolet Colorado, Ford Ranger, Jeep Gladiator, Nissan Frontier and Toyota Tacoma, giving none a good rating.

Its test found that small trucks’ rear seatbelts are to blame for compromised safety.

“A common problem was that the rear passenger dummy's head came dangerously close to the front seatback, and in many cases, dummy measurements indicated a risk of neck or chest injuries,” said IIHS President David Harkey. “All these things tell us that the rear seat belts need improvement.”

The Frontier was given an acceptable rating, but the Ranger was rated marginal, and the Colorado, Gladiator and Toyota poor.

IIHS updated the crash test last year after research found that in newer vehicles, risk of fatal injury is higher for belted occupants in the rear than for those in the front because the front has improved airbags and more advanced seatbelts not usually included in the rear. In the test, all five models showed good protection in the front seat.

The nonprofit said that the rear seat is still the safest for young children.

A good rating in the test can be achieved only with no excessive risk of injury to the head, neck, chest or thigh.

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