(Reuters) - The National Football League's research into the dangers of head injuries undercounted diagnosed concussions, making them appear less frequent than they actually were, the New York Times reported on Thursday.
The newspaper, citing confidential data that it obtained, said an investigation showed the U.S. professional football league omitted more than 100 diagnosed concussions from studies the league commissioned from its teams, including severe injuries to stars like quarterbacks Steve Young and Troy Aikman.
NFL officials could not immediately be reached by Reuters for comment.
The Times said that when it asked the league about the missing cases - more than 10 percent of the total - officials acknowledged the teams were not required to submit their data and some did not.