The power is invisible, but its effects can be seen everywhere, especially in the medical records of active duty military personnel.
Examining the details of 1.5 million emergency room visits at U.S. military hospitals across the country, researchers found that doctors invested significantly more resources on patients who outranked them than on patients of equal or lower rank. The additional clinical effort devoted to powerful patients came at the expense of younger patients, who received worse care and were more likely to become seriously ill.
Military rank was not the only form of power that resulted in unequal treatment. Researchers documented that patients fared better when they shared the same race or gender as their doctor, a pattern that tended to favor white men and caused doctors to fail black patients in particular.
The results were published Thursday in the journal Science.
The findings have implications far beyond the military, said Manasvini Singh, a health and behavioral economist at Carnegie Mellon University who conducted the research with Stephen D. Schwab, an organizational health economist at the University of Texas at San Antonio.
For example, they may help explain why black students do better in school when taught by black teachers, and why black defendants receive more impartial treatment by black judges.
“We think our results apply to many settings,” Singh said.
Disparities generated by power imbalances are easy to detect, but difficult to study in real-world settings.
“It's just hard to measure power,” Singh said. “It's abstract, it's complicated.”
That's where military health records come in.
The Military Health System operates 51 hospitals throughout the country. The doctors who treat them are active duty personnel, as are many of the patients they treat. Comparing their ranks gave Singh and Schwab a useful way to gauge the power differential between doctors and those in their care.
The researchers limited their analysis to patients who sought treatment in emergency departments, where patients are randomly assigned to doctors. That randomness made it easier to measure how power influenced the treatment patients received.
To further isolate the effects of power, the researchers made comparisons between patients of the same rank. If they outranked their doctor, they were considered a “high-power” patient. Otherwise, they were classified as “low power” patients.
Medical records showed that doctors put 3.6% more effort into treating high-power patients than low-power patients. They also used many more resources, such as clinical tests, scans and procedures, according to the study.
Those extra resources translated into better care: High-powered patients were 15% less likely to become sick enough to be admitted to the hospital over the next 30 days.
To see if they could replicate their results, Singh and Schwab focused on doctors who treated patients within a one-year period before or after the patients were promoted to a higher rank. The researchers found that doctors spent 1% more effort on patients after the promotion, as well as more medical resources. Those differences may have been small, but statistically significant, Schwab said.
Next, the pair considered what happened to the low-power patients while the high-power patients received additional care. One hypothesis was that ordering additional tests for one patient could cause doctors to order the same tests for everyone they treated that day. It was also possible that the decisions doctors made for their high-power patients did not influence other patients.
Neither turned out to be the case. Instead, the extra effort invested in high-power patients was diverted from low-power patients, who got 1.9% less effort from their doctors. On top of that, the risk of needing to return to the emergency room or be admitted to the hospital over the next 30 days increased by 3.4 percent, the researchers found.
“The powerful unknowingly 'steal' resources from less powerful individuals,” Schwab and Singh wrote.
Outside the military, doctors and patients cannot use official rank to measure their power against each other, but they do face the effects of race and gender. That led the researchers to investigate whether doctors in their study treated patients differently if they shared these attributes.
The researchers found that white doctors devoted more effort to white patients than to black patients overall. The gap was the same regardless of whether the doctor was higher or lower in rank than the patient.
However, white doctors increased their efforts to treat high-power patients in the same amount, regardless of their race. As a result, white doctors treated high-power black patients the same way, on average, as low-power white patients.
The story was different for black doctors. When they outranked their patients, they spent essentially the same amount of effort on everyone. But on the rare occasions when they encountered a higher-ranking black patient, the amount by which they increased their efforts was more than 17 times greater than when they treated a higher-ranking white patient.
It is unclear what accounts for this “unusual effort,” the researchers wrote. They speculated that since black military personnel were underrepresented among the high-powered patient group, black doctors were particularly attuned to their status.
The effects of gender were more difficult to determine, since biology dictates that men and women require different types of care.
Both male and female doctors invested the greatest effort in the patients who surpassed them in classification. But male doctors improved their care for high-power patients of both sexes to a much greater extent than female doctors. And unlike female doctors, male doctors devoted more effort to female patients in general.
Finally, the researchers asked whether doctors gave preferential treatment to high-power patients because of their elevated status or because those patients had the authority to cause problems if they were dissatisfied with their care. To draw inferences, they compared the treatment of retirees (who retained their status but had given up their authority) with the treatment of active-duty patients (who still had both).
Schwab and Singh found that high-power patients continued to request extra effort from doctors up to five years after they retired, suggesting that status was an important factor.
“I think it's really cool that even after retirement you still have these effects,” said Joe C. Magee, a professor of management and organization at New York University's Stern School of Business, who studies the role of the hierarchy. He sees this as a strong sign that status drove doctors' decisions all along.
“What these people can demonstrate is that it has real health consequences,” Magee said.
Eric Anicichprofessor of management and organization at the USC Marshall School of Business, called the study “impressive” and the findings “important.”
Although a 3.5% increase or 1.9% decrease in physician effort may seem small, its cumulative impact is significant, especially when it comes to something as important as healthcare, he said.
The inequalities documented in the study are not unique to doctors or the military, Schwab and Singh said. The mathematical model they developed to describe behavior in military emergency rooms also helps explain why people in all types of situations give preferential treatment to people who look like them: it may help minimize the effects of disparities. social.
In a commentary accompanying the study, Laura Nimmon of the Center for Health Education Scholarship at the University of British Columbia wrote that “the ephemeral and unobservable nature of power has made its study profoundly difficult.” But she said it's worth the effort to ensure doctors exercise their power more fairly.
The disparities reported by Schwab and Singh are “a cause for serious concern for society at large,” he wrote.
