The McGaw Medical Center, an umbrella group for the five institutions in which Northwestern medical students receive their on-site training, is as a defendant in a class-action antitrust lawsuit, an administrator said Tuesday.

The lawsuit, filed May 7 in Washington, alleges that seven medical organizations and more than 1,000 private hospitals use a national program that matches medical school graduates to their residency sites to overwork and underpay them.

Thomas Cline, NU’s general counsel, said he was not sure why McGaw was named a defendant.

“At this point it’s a little difficult to tell what the plaintiffs’ strategy is in who they named,” Cline said.

The center oversees Evanston Northwestern Healthcare, Children’s Memorial Hospital, Northwestern Memorial Hospital, the Rehabilitation Institute of Chicago and Veterans Affairs Chicago Health Care System-Lakeside Division.

The center and the university are separate, said Alan Cubbage, vice president for university relations.

Northwestern Memorial Hospital and Evanston Northwestern Healthcareare are corporate entities separate from the university, Cubbage said.

The groups do, however, work closely together, he said.

“It’s all very interrelated,” Cubbage said.

“We share Northwestern in our title, and Northwestern medical students get their medical training there,” he said.

Almost all members of the medical staffs at the five institutions have faculty appointments at NU’s medical school.

It is too early to gauge what kind of impact the lawsuit could have, Cubbage said.

Robert Christopher, executive director of the McGaw Medical Center, could not be reached for comment.