While there are some 20,000 former N.F.L. players affected by the potential settlement with the league, there are close to four million former college athletes, 1.4 million of them in contact sports. Their experiences vary drastically, Berman said, making monetary damages difficult to address.

“It’s hard to create one class that includes swimmers and football players, given how different their athletic careers are,” said Berman, who added that the N.C.A.A., too, wanted only to discuss policy changes rather than financial rewards. “We felt individuals remain best off bringing individual suits, which they can still do.”

Several cases criticizing the N.C.A.A.’s handling of concussions began in 2011 when the former Eastern Illinois football player Adrian Arrington said the N.C.A.A. had been negligent in educating and protecting him after he sustained multiple concussions. Derek Owens, a wide receiver at Central Arkansas, soon brought his own suit, as did a female soccer player and a hockey player. A number of similar lawsuits were consolidated earlier this year.

According to N.C.A.A. documents uncovered during discovery, there were more than 30,000 concussions at colleges from 2004 to 2009. Describing the organization’s concussion policy, David Klossner, the N.C.A.A.’s director of health and safety, wrote in a 2010 email to a colleague: “Since we don’t currently require anything all steps are higher than ours.”

“A national policy is a very good thing,” said Matthew J. Mitten, the director of the National Sports Law Institute and the former chairman of an N.C.A.A. committee on safety. “We were only able to make simple recommendations, but now there is consensus among the athletic and medical community. The trick will be enforcing it at every school and not just at Ohio State and U.S.C.”

Settlement talks occurred during four meetings over the last year (three with the same judge who mediated the N.F.L.’s concussion settlement). Other terms of the agreement include $5 million for concussion research, to be funded by the N.C.A.A. and its member universities (the $70 million monitoring fund would be paid for by the N.C.A.A. and its insurers). Increased concussion tracking by universities and a preseason baseline test for every athlete would also be required.

To qualify for a neurological exam, former athletes must complete a questionnaire designed by a team of neurologists and concussion experts. Should players qualify and need additional treatment, they can seek it through their own insurance or file a damages claim.