Blacks are less likely than whites to receive quality health care, according to a study conducted by researchers at the Harvard School of Public Health and Harvard Medical School.

Researchers found differences in the frequency of certain medical treatments administered to black and white patients on managed health care plans. The study then correlated frequency with quality of care.

For example, breast cancer screening among the study participants was done for about 63 percent of blacks compared to 71 percent of whites. Eye exams were given to 44 percent of black patients with diabetes compared to 50 percent for whites with the condition.

Beta-blockers were administered after heart attack to 64 percent of blacks compared to 74 percent for whites. And follow-up after hospitalization for mental illness was performed for 33 percent of blacks compared to 54 percent for whites.

“I was surprised by the consistency of disparities across all four measures,” said Eric C. Schneider, lead author of the study and an instructor at the Harvard School for Public Health.

He said the study is also the first to look at the prevalence of continuing treatment for managed health care patients who have been hospitalized for mental illness.

“Mental health follow-ups, the area with the largest gap in care, had never been studied before,” Schneider said.

But Schneider said that the study’s disparities did not result from racial factors alone.

“The breast cancer screening varied by plan and not by race,” Schneider said.

Socioeconomic and educational differences also contributed to “differences in clinical quality of care,” according to a press release from the School of Public Health.

Schneider said he hoped to control for some of these factors by including Medicaid patients in the study. Blacks, he found, received more infrequent care under Medicaid, as well.

The study, published in today’s Journal of the American Medical Association (JAMA), sampled 305,000 members of various health care plans. Each subject was over age 65.