“These are the data and now we seek to understand the reasons,” Elizabeth G. Nabel, the NFL’s chief health and medical adviser, said in a conference call with reporters.

There were 271 reported concussions suffered by players during the 2015 preseason and regular season, according to the league’s data. That was up from 206 in the 2014 season, an increase of 32 percent. There were 229 reported concussions in 2013 and 261 in 2012.

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The sharpest increase came in regular season games. There were 182 reported concussions suffered in regular season games in 2015, up 58 percent from the 115 suffered last season.

“We’ll pore over the numbers. … We’ll look for ways to improve the health and safety of our players,” said Jeff Miller, the NFL’s senior vice president of health and safety policy.

Miller said the NFL has greatly increased the amount of concussion-related screenings undergone by players and is seeing an unprecedented level of concussions being reported by players. Doctors also might be putting players into the league’s concussion protocol more readily, he said.

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“These are factors,” Miller said. “These are issues that we’re going to pursue.”

Richard G. Ellenbogen, the co-chairman of the NFL’s head, neck and spine committee, said those within the sport have become better educated about the dangers of head injuries.

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“I think the education is working,” Ellenbogen said. “I think we’re lowering the threshold” of when a concussion is reported.

Said John York, the co-chairman of the San Francisco 49ers and the chairman of the NFL owners’ health and safety committee: “We must uncover whether our players suffered more concussions this year and if so, why. … Our work will be guided by the data and the experts.”