Are medical residents "students"?

From Inside Higher Ed: Big Legal Victory for Teaching Hospitals:

Universities and hospitals that train doctors won a potentially huge victory Friday in a long-running, many-million-dollar legal fight with the Internal Revenue Service.

The ruling by the U.S. Court of Appeals for the 11th Circuit vacated a lower federal court’s 2005 decision that medical residents are in all cases required to pay Social Security taxes on their wages. The lower court’s ruling — which clashed with a 1998 decision by another federal appeals court that had been seen as the prevailing legal precedent — had been embraced by the Internal Revenue Service in its push to force teaching hospitals to pay tens (if not hundreds) of millions of dollars in back taxes....

We reject the government’s assertion that courts should defer to a ‘bright line’ rule that medical residents can never be exempted from [Federal Insurance Contributions Act] taxation as students,” the appeals panel added. “Instead, a case-by-case analysis is necessary to determine whether a medical resident enrolled in a [graduate medical education] program qualifies” for a student exemption.

The appeals court directed the lower court to rule specifically on whether “Mount Sinai qualifies as a ’school, college, or university’ and whether the Mount Sinai residents qualify as ’students.’ ” (Florida’s Mount Sinai does not award medical degrees, unlike the similarly named institution in New York with which it is not affiliated.)