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 included the design of practice drills and which helmets players were wearing.