Burnout among U.S. doctors is getting worse, according to a study that shows physicians are worse off today than just three years earlier.

Mayo Clinic researchers, working with the American Medical Association, compared data from 2014 to measures they collected in 2011 and found higher measures on the classic signs of professional burnout. More than half of physicians felt emotionally exhausted and ineffective. More than half also said that work was less meaningful.

The data dovetail with a recent JAMA study, which found much greater prevalence of depression among doctors in training than in the general population.

Taken together, experts say the problems require solutions that offer a systemic approach. All health care organizations have a shared responsibility to address the situation, they add.

"What we found is that more physicians in almost every specialty are feeling this way and that's not good for them, their families, the medical profession or patients," said Tait Shanafelt, an author of the Mayo study and director of the clinic's Department of Medicine Program on Physician Well-being. The study was published in Mayo Clinic Proceedings.

The results were based on survey responses from 6,880 physicians across the United States. In the 2011 survey, 45 percent of doctors met the burnout criteria, with highest rates occurring in the fields considered the "front lines," such as general internal medicine, family medicine and emergency medicine.

In 2014, 54 percent of responding physicians had at least one symptom of burnout.

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