Flawed algorithm leads to large racial disparities in health care access, study finds

A study published this week found that healthcare algorithm makes black patients substantially less likely than their white counterparts to receive important medical treatment (Source: “A health care algorithm affecting millions is biased against black patients,” The Verge, Oct. 24, 2019).

The study, published in the journal Science, does not name the makers of the algorithm, but Ziad Obermeyer, an acting associate professor at the University of California, Berkeley, who worked on the study says “almost every large healthcare system” is using it, as well as institutions such as insurers. Similar algorithms are produced by several different companies as well. “This is a systematic feature of the way pretty much everyone in the space approaches this problem,” he says.

The algorithm is used by health care providers to screen patients for “high-risk care management” intervention. Under the system, patients who have especially complex medical needs are automatically flagged by the algorithm. Once selected, they may receive additional care resources, like more attention from doctors. To make that prediction, the algorithm relies on data about how much it costs a care provider to treat a patient. In theory, this could act as a substitute for how sick a patient is. But by studying a dataset of patients, the authors of the Science study show that, because of unequal access to health care, black patients have much less spent on them for treatments than similarly sick white patients. The algorithm doesn’t account for this discrepancy, leading to a startlingly large racial bias against treatment for black patients.

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