That suggests fewer generalists will be entering the workforce, researchers said - possibly exacerbating the primary care doctor shortage in parts of the United States.

"I think this was a much needed, long overdue paper, and really kind of eye-opening," said economist and health policy researcher Amitabh Chandra from Harvard University in Cambridge, Massachusetts.

The study "tells us yet again that simple solutions to the problems with shortages in the primary care workforce are unlikely to give us the results that we want," Chandra, who wasn't involved in the new research, told Reuters Health.

For the study, researchers at the Mayo Clinic in Rochester, Minnesota analyzed surveys of close to 17,000 young doctors who were in the final year of an internal medicine residency program.

Of those residents, just under 22 percent said they were planning on becoming a general internal medicine doctor. Another 64 percent wanted to be a specialist, most often a heart or lung doctor or an oncologist. The rest hoped to work in a hospital, or were undecided about their future.

Women were more likely to report a plan to stay in internal medicine than men.

Compared to the same residents' survey responses two years earlier, changes in career plan into or away from general internal medicine were both common, Mayo Clinic's Dr. Colin West and Dr. Denise Dupras reported Tuesday in the Journal of the American Medical Association.

"There have been recent estimates that in the next decade or so, we may be as much as 50,000 primary care physicians short in the United States," West said.

That's due to a combination of factors, such as older doctors retiring and more people getting insurance through health care reform and needing a general doctor, he told Reuters Health.

"Our study suggests that current numbers of graduates planning general medicine careers won't come anywhere near meeting that shortage," West said.

SALARY DIFFERENCES

Chandra said some young doctors may graduate medical school hoping to be a primary care physician, but realize during residency that it's much more lucrative to go into a specialty such as cardiology or ophthalmology. Others might plan to be a specialist all along, but find it easier to get into an internal medicine residency program than a competitive specialty one.

Thus, training more internal medicine residents might not be the answer to doctor shortages, researchers said. Another strategy, according to Chandra, is to find ways to get current primary care doctors into specific areas of the country that are underserved - and to pay those doctors more to work slightly longer hours and see extra patients.

"Ultimately... we just have to start to pay much more to general internal medicine physicians," he said.

Others have suggested that nurse practitioners and physician assistants could fill the gap.

According to the U.S. Bureau of Labor and Statistics, the average annual salary for a primary care doctor in 2010 was $202,392, compared to $356,885 for all medical specialists combined.

Another recent study from Chandra and his colleagues suggested that growth in primary care doctors' salaries is lagging compared to pay for others in the health care field, such as dentists and pharmacists (see Reuters Health story of November 27, 2012: reut.rs/WtUn8L).

West said righting the primary care doctor shortage may require system-wide changes, such as paying physicians for better patient outcomes, instead of for performing more procedures.

"We really need to put much more attention into revitalizing internal medicine and primary care as viable career options," he said.

SOURCE: bit.ly/MvXYT6 Journal of the American Medical Association, online December 4, 2012.

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