Despite a critical shortage of primary care in the United States, less than 25 percent of newly minted doctors go into this field and only a small fraction, 4.8 percent, set up shop in rural areas, says a study by researchers at the George Washington University School of Public Health and Health Services, in Washington, D.C.

Those findings, from areport released last month in the "Published Ahead-of-Print" section of an online edition of Academic Medicine, suggest the nation's output of primary care physicians falls short of a demonstrated need and will be unable to solve the growing shortage in underserved areas anytime soon.

"If residency programs do not ramp up the training of these physicians, the shortage in primary care, especially in remote areas, will get worse," says lead study author Dr. Candice Chen, an assistant research professor of health policy at George Washington University. "The study's findings raise questions about whether federally funded graduate medical education institutions are meeting the nation's need for more primary care physicians."

The nation's graduate medical education system (GME) relies on public funding, including nearly $10 billion in funds from the Medicare program and another $3 billion from Medicaid. Despite the large infusion of cash, experts have said that the federal government doesn't hold residency programs accountable for producing physicians trained to serve in rural or underserved parts of the country. Even though Medicare and Medicaid represent the largest public investment in the U.S. health workforce, there are still serious shortfalls in the number of primary care physicians in some geographical regions and in other high need specialties such as general surgery.

Chen and her colleagues studied the career paths of almost 9,000 physicians who had graduated from 759 medical residency sites from 2006 to 2008. The researchers analyzed data to find out where those new physicians ended up practicing three to five years after graduation. They found that overall, only 25 percent of the physicians in this study worked as primary care doctors, although that number likely is an overestimate because it includes graduates who practice as hospitalists, Chen says.

In addition, the researchers found that 198 out of 759 institutions produced no rural physicians at all during the study period. And 283 institutions graduated no doctors practicing in Federally Qualified Health Centers, clinics that provide care to low-income patients and others—often in remote or struggling urban areas.

About 66 million people in the U.S. live in rural areas or urban neighborhoods that have too few primary care physicians or too little access to primary care in clinics. That's about one in five Americans who lack adequate access to this kind of essential care and might develop more serious health conditions as a result, Chen says.

Chen asserts the U.S. currently is producing primary care physicians at rates that are abysmally low, and unless something changes, the nation will have an even greater shortfall of primary care doctors just as the Affordable Care Act (ACA) ramps up demand for those services. Already rural and urban clinics in underserved neighborhoods struggle to find and retain primary care doctors.

The new study underscores the growing disconnect between federal funding to pay for residency programs and the nation's shortage of primary care doctors, researchers contend. The study also found that the top 20 primary care producers in this study trained 1,658 primary care doctors, or 41 percent, of a total of 4,044. Those sites received just $292 million in GME funding.

In contrast, the bottom 20 programs produced only 684 primary care graduates out of 10,937, equating to 6.3 percent. Yet the study notes those sites received a whopping $842 million in GME payments—an amount that reflects not a dedication to training doctors in primary care but in churning out highly paid specialists who typically practice in big cities or the suburbs, the researchers assert.

Chen and Dr. Fitzhugh Mullan, also of George Washington University, say that almost two-thirds of the nearly $10 billion in Medicare funding for GME annually goes to 200 hospitals—and those sites perform poorly in producing primary care doctors. Policymakers should take a hard look at the skewed incentives and other factors that have led to the current primary care crisis and develop a more accountable GME system, the study authors say.

"Better balance in medical specialties and more primary care physicians will be essential to building an effective and affordable health system going forward," Mullan says.

Established in July 1997, George Washington's School of Public Health and Health Services brought together three longstanding university programs in the schools of medicine, business, and education and is now the only school of public health in the nation's capital.