The number of concussions suffered by NFL players, including the Texans’ Tom Savage, was up from last season (AP/David J. Phillip)

The number of diagnosed concussions suffered by NFL players increased nearly 16 percent this season over last season, and the rate of injuries suffered by players during Thursday night games exceeded the injury rate in other games.

Those were among the key developments as the NFL released its preliminary injury data Friday for the 2017 preseason and regular season.

“Certainly we’re disappointed that the concussion numbers are up. … We take this as a challenge because we’re not going to be satisfied until we drive that number much lower,” Allen Sills, the NFL’s chief medical officer, said in a conference calls with reporters.

According to the data, which is gathered and analyzed by the independent company IQVIA (formerly called Quintiles) and also provided to the NFL Players Association, players suffered 281 concussions during the preseason and regular season. That is an increase of 15.6 percent over the 243 diagnosed concussions suffered by players during the 2016 preseason and regular season.

It also is the highest number of concussions suffered by players in a season since at least 2012. According to the data provided by the league, there were 261 concussions suffered by players in 2012, 229 in 2013, 206 in 2014 and 275 in 2015.

Jeff Miller, the NFL’s executive vice president of health and safety, pointed to the sharp increase in the number of concussions suffered by players in practices before the season. That number jumped from 26 in 2016 to 45 in 2017. That increase will lead to a closer examination by the league, Miller said, of the types of drills performed by individual teams during preseason practices.

League officials said they did find it encouraging that players are self-reporting concussion symptoms with greater frequency. About 28 percent of this season’s concussion evaluations were performed as a result of players self-reporting, according to the league’s data, up from 19 percent in 2016.

The injury rate during Thursday night games is closely scrutinized because some players have complained that the games are unsafe due to short rest, after playing the previous Sunday, and should not be played. One of the counterarguments to that contention over the years has been that the injury rate actually has been lower for Thursday games than for other games.

That was not the case this season. There were 6.9 injuries per game on Thursday nights, according to the NFL’s data, compared to 6.3 injuries per game in Saturday, Sunday and Monday games. For an injury to qualify, it had to result in the player being removed from the game or subsequently being sidelined from football activities, the league said.

The injury rate was lower for Thursday games than for other games in each of the 2014, ’15 and ’16 seasons, according to the data. In 2016, there were 5.3 injuries per game on Thursdays, compared to 6.5 injuries per game on other days.

Sills said the sample was too small to draw any conclusions.

“The injury rate is certainly an important metric to track,” Sills said. “But it doesn’t tell the complete story.”

It remains to be seen if players will take a different view. DeMaurice Smith, the NFLPA’s executive director, said in a meeting last January with Washington Post reporters and editors that, despite the pointed criticism by some players, only about half of players at that point opposed Thursday night games. Smith pointed out then that the injury rate, as of that point, was lower for Thursday games.

“I’m not being coy,” Smith said then. “But when somebody asks me what should happen with Thursday night games, I don’t spend a lot of time thinking about it because I don’t get a vote. If Thursday night games are a big issue for our [team-by-team player] reps, they’ll bring it up. If they want to vote on a resolution to do something with Thursday night games — play them, not play them, engage the league about them — that’s what we do.”

The number of knee injuries suffered by players changed little from last season to this season. According to the injury data, players suffered 54 anterior cruciate ligament tears during the 2017 preseason and regular season, down from 56 in 2016. The number of MCL tears was slightly up, with 147 this season compared to 143 during the 2016 season.

That might be a bit surprising, given the focus during this season on the injuries suffered by high-profile players such as Carson Wentz, Deshaun Watson, Aaron Rodgers, Odell Beckham Jr. and J.J. Watt. Wentz, a league MVP front-runner for the Philadelphia Eagles, and fellow quarterback Watson, an offensive rookie of the year favorite for the Houston Texans, had their season ended by anterior cruciate ligament tears.

But league leaders always had taken a wait-and-see approach on the overall injury rate.

“I’ve been in it a long time,” Atlanta Falcons President Rich McKay, the chairman of the NFL’s rulemaking competition committee, said at an owners’ meeting last month in Dallas. “So I’ve seen plenty of years when there’s been a lot of high-profile injuries. Every year that I kind of think, ‘Boy, the injury numbers are higher than usual,’ I’m surprised at the end of the year that they’re not. So I am one that says withhold [judgment] until you see the final numbers.

“And then I think you do go back and you look by position of, ‘Is there some trend there? Is it quarterbacks? Is it lower-leg injuries to quarterbacks? Did it happen inside the pocket? Outside the pocket?’ Because I think all that data can lead you to a point where sometimes you say, ‘You know, we need to change something because a certain type of injury is happening to a certain type of player in a certain type of play.’ I don’t know. I haven’t seen anything that says that yet. And so I think I’d just want to be one that says because I’ve been burned before [by jumping to conclusions about injuries], I want to wait and see.”

Sills said Friday the injury numbers will be studied more closely in the coming weeks.

“This is preliminary data,” Sills said. “We’re going to have a lot more detail placed into this.”

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