ASHINGTON, March 20 — Racial and ethnic minorities in the United States receive lower quality health care than whites, even when their insurance and income are the same, say a panel of scientific experts who termed their study a wake-up call to the nation's doctors.

The study, made public today by the Institute of Medicine, an independent research institution that advises Congress, is the first comprehensive look at racial disparities in health care among people who have health insurance.

While the so-called race gap in medicine has been well-documented, previous research has attributed much of the problem to lack of access to care. The panel cited subtle racial prejudice and differences in the quality of health plans as possible reasons why even insured members of minorities get worse care.

"The differences are pervasive," said Martha N. Hill, director of the Center for Nursing Research at Johns Hopkins University School of Nursing, and the co-vice chairwoman of the panel. "It cuts across all conditions of health and across the entire country, and we think this is a very serious moral issue."

Saying they were deeply troubled by the findings, the authors made recommendations that included additional research to understand how bias affects care, efforts to increase the number of minority doctors, and the use of interpreters to ease communication between physicians and patients who do not speak English.

The report, which reviewed more than 100 studies conducted over the last decade, concluded that the disparities contribute to higher death rates among minorities from cancer, heart disease, diabetes and H.I.V. infection.

It found that members of minorities were less likely to be given appropriate medications for heart disease, or to undergo bypass surgery, and are less likely to receive kidney dialysis or transplants than whites. They are also less likely to receive the most sophisticated treatments for infection with H.I.V., which could delay the onset of AIDS.

But members of minorities are more likely to receive certain less desirable procedures. The committee cited a study of Medicare beneficiaries, for instance, that found blacks were 3.6 times as likely as whites to have their lower limbs amputated as a result of diabetes.

"Some of us on the committee were surprised and shocked at the extent of the evidence," said the chairman of the panel, Dr. Alan R. Nelson, a former president of the American Medical Association. He added, "The evidence is overwhelming."

But Claude Allen, the deputy secretary for health and human services, said the findings did not surprise federal health officials. Mr. Allen said today that the Bush administration was continuing an initiative begun under President Bill Clinton to erase disparities in medical care.

"We believe that education is the key, both education for providers to be aware of the subjectivity of their decisions and education for patients, to allow them to take control of their health care decision making," he said.

The authors of the study offered multiple explanations for the disparities, among them quality of insurance. Members of minorities are more likely than whites to be enrolled in lower-end insurance plans that impose stricter limits on medical services, and that require doctors to see more patients, spending less time with each.

Yet the study found that differences persist even when minority and white patients have the same insurance, in part because minority patients are less likely than whites to have a long-lasting relationship with a primary care physician.

Racial bias, albeit subconscious, may also be at work, the study found. While the panel said most health providers were well-intentioned, it cited "indirect evidence" that doctors' decisions were influenced by their perceptions of race.

As an example, the authors cited a study of major medical centers in New York State that found African-Americans were 37 percent less likely to undergo angioplasty and other heart procedures, including bypass surgery, than whites. In 90 percent of the cases in which the patient did not get the surgery, the doctor had not recommended it.

In interviews with the doctors, the researchers found "classic negative racial stereotypes," the report said, such as assumptions that black patients would be less likely to participate in follow-up care.

"This is a timely and powerful report," said Dr. Lucille C. Perez, president of the National Medical Association, which represents black doctors. "It validates what the N.M.A. has been saying for so long — that racism is a major culprit in the mix of health disparities, and has had a devastating impact on African-Americans."

A spokeswoman for the American Medical Association, the nation's largest organization representing doctors, declined to comment on the findings, saying its officials had not seen the study. In a policy statement adopted in 1998, the medical association "encourages physicians to examine their own practices to ensure that inappropriate considerations do not affect their clinical judgment."

Although the medical literature is most complete on disparities between African-Americans and whites, the report found the disparities also extended to Hispanics.

Part of the problem, the report said, may be a lack of minority doctors. Minorities, including African-Americans, Asian-Americans, Hispanics and American Indians, account for just 9 percent of the nation's doctors.

David R. Williams, a professor of sociology at the University of Michigan who served on the panel, called the report "a wake-up call" for doctors and patients.

"We have a health system that is the pride of the world," Professor Williams said. "But this report demonstrates that the playing field clearly is not level."