NEW YORK -- The NFL is attacking the concussion issue on a team-by-team basis. At the owners meetings in New York on Tuesday, Dr. Allen Sills, the NFL's chief medical officer, said the league identified seven teams in 2017 that had a higher incidence of preseason concussions than the others and "did a targeted intervention with those clubs." Sills said that process involved wide-ranging discussions with the football operations staffs of the teams that involved the design of practice drills and which helmets players were wearing. "In six of those seven clubs, the numbers did go down," Sills said. "Those seven clubs had 23 practice concussions as a whole in 2017, down to nine in 2018." Overall, the league said, preseason concussions were down from 91 in 2017 to 79 this year, and that there were zero on kickoff plays. The NFL modified its kickoff rules this year to make the play safer, as it traditionally has featured a significantly higher rate of concussions than other plays. "We...