It seems intuitive that going to a specialist physician will result in more thorough and up-to-date care for whatever ails you. In fact, many studies support this idea—but health-care researchers caution that they may not tell the whole story.

The first question is whose patients are sicker? Specialists tend to treat more complicated forms of disease, but generalist—family physicians and general practitioners—are more likely to treat patients with several coexisting diseases.

A second question is what counts as the most valuable treatment? Specialists are more familiar with standards of care for the diseases they treat regularly, says Harlan M. Krumholz of Yale University. On the other hand, a generalist may do a better job of coordinating a patient's care and keeping an eye on a person's overall health, says Martin T. Donohoe of the Oregon Health Sciences University in Portland.

To further complicate comparisons, many generalists will consult with specialists on complicated cases, but medical records do not always show that, says Carolyn Clancy of the Agency for Health Care Policy and Research in Rockville, Md.

That said, stroke patients treated by neurologists are more likely to survive than stroke patients treated by generalists. Among about 38 000 stroke sufferers nationwide, 16.1 percent of those treated by a neurologist died within 3 months, compared with 25.3 percent of those treated by family physicians.

Several studies have shown that people with heart disease fare better when they are treated by cardiologists, says Ira S. Nash of the Mount Sinai Medical Center in New York, but it's hard to figure out exactly why.

"Physician specialty, in addition to being a measure of formal training in the field, is also a proxy for clinical experience," he says. "It's very difficult to separate out the overlapping concepts: one, that practice makes perfect; two, the effect of the educational and time investments in a clinical problem the physician is simply interested in; and three, the issue of formal training."

Differences between specialist care and generalist care, however, pale in comparison with the finding that both specialists and generalists often fail to put the latest knowledge into practice, contend both Donohoe and Clancy. A report by the U.S. General Accounting Office documented that heart attack survivors who saw cardiologists regularly were more likely to take cholesterol-lowering drugs and beta blockers—which reduce heart rate and blood pressure—than those who received care from a generalist. Even so, these life-prolonging drugs were not prescribed to many patients who appeared to be eligible for them, implying that both generalists and specialists could do better.

"Maybe we are focusing too much energy on the differences between generalist and specialist care," says Donohoe. Perhaps, he adds, "we should focus more intently on improving the quality of communication and cooperation between generalists and specialists and on developing and promoting practice guidelines that might have a much bigger effect on the overall health of Americans."