Unlike the NHTSA tests, the Euro NCAP tests include tests of pedestrian, cyclist and motorcyclist protection - both passive protection to mitigate injury in the event of a collision, and active protection to prevent a collision in the first place. Performance in these tests count towards the overall 5 star rating. My understanding is that NHTSA is working on preliminary research into the issue, but they're a clear 15-20 years behind Euro NCAP.

https://www.euroncap.com/en/car-safety/the-ratings-explained...