MONDAY, Oct. 3, 2016 (HealthDay News) -- A doctor's political beliefs can sway his or her treatment decisions.

That's the conclusion of a study by Yale University researchers who surveyed primary care doctors in 29 states on how they would deal with different types of patient health concerns, including abortion, firearms and marijuana use.

While Republican and Democratic doctors had similar views about general issues such as depression, alcohol abuse and obesity, there were significant differences when it came to political hot-button topics.

Republican doctors expressed more concern than Democratic doctors about marijuana use and abortion, while Democratic physicians were more concerned about firearms, the findings showed.

Democratic doctors were more likely to urge patients not to keep guns in the home while Republican doctors were more likely to warn patients about the mental health risks of abortion. Republicans were also more inclined to advise patients to reduce marijuana use and consider the legal risks of using the drug, the study found.

"The evidence suggests that doctors allow their political views to influence their professional decisions in the medical exam room," study co-author Eitan Hersh said in a Yale news release. Hersh is an assistant professor of political science.

"Just as patients choose physicians of a certain gender to feel more comfortable, our study suggests they may want to make a similar calculation based on their doctor's political views," Hersh said.

Study co-author Matthew Goldenberg added that "given the politicization of certain health issues affecting countless patients, it is imperative that physicians consider how their political views may affect their professional judgments."

Goldenberg, an assistant professor of psychiatry, said the study findings indicate the need for more training concerning "biases in how we address politically salient health issues."

The study was published Oct. 3 in the Proceedings of the National Academy of Sciences.

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