Doctors often register unconscious bias against blacks, study finds

Psychological testing shows white physicians have friendlier attitudes toward anonymous white people than toward black people. But is this linked to unequal treatment?

By Kevin B. O’Reilly — Posted Sept. 28, 2009

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White physicians, like white lawyers and white people with doctoral degrees, are not immune from an implicit preference for white people over black people, according to a study in the August Journal of Health Care for the Poor and Underserved.

Psychological testing shows that doctors do not differ from the general population or from other highly educated people in unconscious racial bias, the study said. But critics doubt whether these test results are associated with unequal treatment of black patients. Other research, including a new study of patients with breast or colon cancer, has concluded that disparities are driven not by racial bias, but by differences in where patients get medical care.

Between 2004 and 2006, more than 2,500 doctors took the Implicit Association Test, or IAT, which attempts to measure test-takers' unconscious preferences by asking them to quickly associate "good" words such as joy and love and "bad" words such as evil and nasty with white or black faces. White, Asian and Hispanic doctors showed preferences for whites over blacks, while black physicians showed no significant preference, the study said. These unconscious preferences for whites were two to three times' higher than the physicians' self-reported attitudes.

The gap between physicians' conscious attitudes and their implicit preferences could help explain why black patients receive worse care, said study lead author Janice A. Sabin, PhD.

"People's intentions are very good, but somehow there consistently are disparities in how people are treated based on race and ethnicity," said Sabin, acting assistant professor at the University of Washington's Dept. of Medical Education and Biomedical Informatics. "Physicians may be like others and hold unconscious associations, and under certain conditions, such as a heavy workload, these unconscious associations may guide decisions in a way that's hidden, in a way that the person's not even aware."

Physicians and other highly educated people "wouldn't be biased generally, but these unconscious associations are pretty pervasive in society," Sabin said.

Sabin said doctors could use findings about their implicit preferences to help them learn skills to relate better to patients as individuals rather than as members of racial or ethnic groups. But other experts doubted the usefulness of the study's findings.

"There is no attempt in the study to associate those with high or low scores with any particular medical practice," said Hal R. Arkes, PhD, professor of psychology at Ohio State University, who specializes in research on medical decision-making. "A high score on the IAT could mean any number of things, and being a bigot could be one of them. Articles pertaining to physicians in the past didn't compel that conclusion."

Arkes engaged in a heated debate over interpretation of data in a September 2007 Journal of General Internal Medicine study that drew a link between greater bias against blacks and lower likelihood of black patients receiving appropriate thrombolytic treatment for acute coronary symptoms. He believes that proof of a connection between IAT scores and racially motivated medical treatment is lacking.

Disparities have a dollar impact

The debate is far from academic. If physicians' unconscious attitudes are responsible for driving unequal treatment, then tackling the problem through training or other methods could save money, according to a September study released by the Joint Center for Political and Economic Studies, a Washington, D.C., think tank.

Racial health disparities in infant mortality, chronic disease and many other metrics cost the U.S. health system more than $57 billion a year, said the report, authored by researchers from Johns Hopkins University and the University of Maryland.

Previous research, such as a June 25 Archives of Internal Medicine study of 123 hospitals caring for more than 320,000 patients, found that quality performance was about the same across race and ethnicity after adjusting for where minority patients sought care. That is, economic disparities in hospital funding principally account for unequal treatment.

An Aug. 20 Journal of Clinical Oncology study seems to buttress that finding. The study found that disparities in patient mortality after breast or colon cancer surgery were mostly explained by hospital quality.

"The hospitals that treated a larger percentage of black patients had worse survival outcomes, whether those were black or white patients," said Tara M. Breslin, MD, lead author of the study and a surgical oncologist at the University of Michigan. "The system that provides the care may somehow not be as efficient at getting patients through the system and giving patients timely surgery, timely therapy and complete courses of adjuvant therapy."

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Aiming for zero bias

Psychological testing found that white, Asian and Hispanic doctors have a significant subconscious, implicit preference for white people over black people. On the testing scale, a zero means no preference for whites or blacks. The higher the score, the greater the preference for whites.

Race/ethnicity Tested bias
White 0.44
Black 0.05
Asian 0.40
Hispanic 0.40

Source: "Physicians' Implicit and Explicit Attitudes About Race by MD Race, Ethnicity, and Gender," Journal of Health Care for the Poor and Underserved, August (link)

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External links

"Hospital Factors and Racial Disparities in Mortality After Surgery for Breast Cancer and Colon Cancer," abstract, Journal of Clinical Oncology, Aug. 20 (link)

"Implicit Bias among Physicians and its Prediction of Thrombolysis Decisions for Black and White Patients," abstract, Journal of General Internal Medicine, September 2007 (link)

"Physicians' Implicit and Explicit Attitudes About Race by MD Race, Ethnicity, and Gender," abstract, Journal of Health Care for the Poor and Underserved, August (link)

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