“This proposal is likely to penalize physicians who treat sicker patients, even though they spend more time and effort and more resources managing those patients,” said Deborah J. Grider, who has audited tens of thousands of medical records and written a book on the subject.

Dr. Atul Grover, the executive vice president of the Association of American Medical Colleges, said, “The single payment rate may not reflect the resources needed to treat patients we see at academic medical centers — the most vulnerable patients, those who have complex medical needs.”

While the proposal would redistribute money among doctors, it is not intended to cut spending under Medicare’s physician fee schedule, which totals roughly $70 billion a year.

If the new rules really do simplify their work, doctors say, they will be elated.

“We can focus more on patient care and less on the administrative burden of documentation and billing,” said Dr. David B. Glasser, an assistant professor of ophthalmology at the Johns Hopkins University School of Medicine. “We sometimes joke that it can be more complicated trying to get the coding level right than it is to figure out what’s wrong with the patient.”

But, Dr. Glasser said, the financial impact of the proposal on eye doctors is not yet clear.

Documentation requirements have increased in response to growing concerns about health care fraud and improper payments that cost Medicare billions of dollars a year.

In many cases, federal auditors could not determine whether services were actually provided or were medically necessary. In some cases, they found that doctors had billed Medicare — and patients — for more costly services than they actually performed.

In a report required by federal law, officials estimated early this year that 18 percent of Medicare payments for office visits with new patients were incorrect or improper, about three times the error rate for established patients.