Elderly patients have better outcomes when hospitalized if cared for by a female physician than a male, according to a Harvard University study published in JAMA Internal Medicine.

The researchers examined a random sample of 1.5 million Medicare hospitalizations between 2011 and 2014. Patients who saw a female physician were 4 percent less likely to die and 5 percent less likely to be readmitted within 30 days. The difference was great enough that researchers said if male physicians achieved the same outcomes as their female counterparts, 32,000 fewer patients would die every year.

“The difference in mortality rates surprised us,” said Yusuke Tsugawa, research associate in Harvard’s Department of Health Policy and Management and the study’s lead author. “The gender of the physician appears to be particularly significant for the sickest patients. These findings indicate that potential differences in practice patterns between male and female physicians may have important clinical implications.”

The study said the correlation remained consistent across many clinical conditions and among variations in severity. The association was seen across a wide variety of clinical conditions and variations in severity of illness. When restricting the analysis to the randomly assigned patients under a hospitalist’s care, the results stayed the same, ruling out patient selection as a factor.

It’s not the first time differences have been discovered between physicians of different genders. As the study pointed out, female doctors are more likely to follow clinical guidelines and evidence-based care.

While the results may appear to say female physicians are better at caring for patients than their male colleagues, experts not involved in the study warned against jumping to such a conclusion.

“It would be a mistake to change anything in public policy on the basis of these results, or to advise patients to change their behavior based on this information alone,” Mark Friedberg, RAND Corporation senior natural scientist, said to Kaiser Health News.

In an accompanying op-ed, however, researchers said hospitals should draw one gender-based conclusion from the study: There’s no justification for the pay gap between male and female physicians.

“These findings that female internists provide higher quality care for hospitalized patients yet are promoted, supported and paid less than male peers in the academic setting should push us to create systems that promote equity in start-up packages, career advancement, and remuneration for all physicians,” wrote Anna Parks, MD, of the University of California, San Francisco’s internal medicine department and JAMA editor Rita Redber, MD. “Such equity promises to result in better professional fulfillment for all physicians as well as improved patient satisfaction and outcomes.”