Pedestrian automatic emergency braking systems (AEB) don’t work as well in the dark, according to the Insurance Institute for Highway Safety (IIHS).

The organisation conducted nighttime tests on 23 midsize cars, midsize SUVs and small pickups. Four were awarded the highest rating of superior, but more than half received a basic score or no credit.

In the daylight test, 19 of the 23 vehicles earned superior or advanced ratings.

“As we expected, most of these pedestrian AEB systems don’t work very well in the dark,” said IIHS President David Harkey.

The nighttime test included two common pedestrian crash scenarios, an adult crossing the road and an adult walking along the road at the edge of the travel lane.

The crossing test was conducted at 12 mph and 25 mph, and the parallel test conducted at 25 and 37 mph. Scores were awarded based on the average speed reductions in five repeated test runs on dry pavement.

Separate trials were conducted with the headlights on the high beam and low beam settings.

According to the IIHS, pedestrian fatalities continue to rise since reaching a low point in 2009. Federal estimates for 2021 show pedestrian crash deaths have soared nearly 80 percent. The approximately 7,300 pedestrians killed in 2021 accounted for almost a fifth of all traffic fatalities.

Three-quarters of those fatalities occur at night, IIHS said.

The organisation has announced that an advanced or superior rating in the nighttime test will become a requirement for the TOP SAFETY PICK+ award in 2023.

Full results from the nightime tests can be viewed on the IIHS website.