Researchers found a 54 percent difference in concussion risk between two different helmets made by the same company in a large study that included data from 1,833 college football players.

The players in the study wore one of two helmet models made by the Riddell company: the older VSR4 and the newer Revolution. All the helmets had been equipped with sensors that recorded forces, or accelerations, experienced by the players’ heads each time there was a hit.

“No helmet can completely prevent concussions,” said study co-author Stefan Duma, a professor and head of biomedical engineering at Virginia Tech-Wake Forest University. “There’s always a risk. All we are saying is that by effectively adding more padding, it reduces the accelerations, and that reduces concussions.”