The Insurance Institute for Highway Safety (IIHS) is updating its longest-running crash test, the moderate overlap front evaluation, by adding a test dummy to the back seat.

The move aims to address a growing gap in the protection provided for front and rear occupants.

The organisation tested 15 small SUVs with the new addition which saw only two, the Ford Escape and Volvo XC40, receiving a good rating.

The Toyota RAV4 earned an acceptable rating, and the Audi Q3, Nissan Rogue and Subaru Forester were rated marginal. Another nine vehicles — the Buick Encore, Chevrolet Equinox, Honda CR-V, Honda HR-V, Hyundai Tucson, Jeep Compass, Jeep Renegade, Mazda CX-5 and Mitsubishi Eclipse Cross — were rated poor.

Previously all 15 vehicles earned good ratings in the original evaluation.

“The original moderate overlap test was our first evaluation and the lynchpin of the Institute’s crash testing program,” said IIHS President David Harkey.

“Thanks to automakers’ improvements, drivers in most vehicles are nearly 50 percent less likely to be killed in a frontal crash today than they were 25 years ago. Our updated test is a challenge to manufacturers to bring those same benefits to the back seat. The stellar performance of the Escape and XC40 shows it’s possible.”

The full results of the test can be read on the IIHS website.