Behind the change of heart lies a cadre of economists and physicians who argue that demographic changes will make doctors scarce. First and foremost, they say, the population is expanding and the Baby Boomers are aging, resulting in more people to care for—especially more old and sick people. Doctors are aging too, and many are retiring. Add to that a decline in the number of hours physicians are willing to put in each day and a few incipient signs of a shortage (notably longer waiting times for appointments and rising salaries for young doctors), and the conclusion that we should expand the physician workforce seems like a no-brainer.
And it would be, if not for all the complications. Those incipient signs, many experts note, may suggest something other than a shortage, and the projections for the number of doctors we’ll need aren’t all that clear-cut. Some experts would even go so far as to suggest we need fewer doctors, not more. Elliott Fisher, a physician and researcher at the Center for Evaluative Clinical Sciences at Dartmouth Medical School, quipped at a recent gathering at the Institute of Medicine, “If we sent 30 percent of the doctors in this country to Africa, we might raise the level of health on both continents.”
The physician workforce estimates rest on two critical assumptions, both of which are probably wrong.
The first is that the number of doctors practicing today is about right and that the market would send signals if supply were exceeding demand. This seems sensible enough, at least on the face of it. For most goods and services, after all, supply in any given community is limited by demand, a measure both of how much consumers need or want the product and of how able they are to pay for it. The number of car dealers in your town, for instance, depends on the number of people who want cars and can afford them.
The ability of patients to pay does help determine the number of doctors in any given community; physicians tend to congregate in places where incomes are higher and patients are more likely to be insured. (And to be sure, physicians are in short supply in parts of the country where relatively few people have health insurance, especially rural areas.) But the other component of demand—how much health care patients want or need—has far less influence over the supply of physicians. That’s because for the most part it’s your doctor and not you, the consumer, who determines how much care you receive. When your doctor says you need a CT scan, you get one. When your doctor says you should go to the hospital, you go. Doctors, in effect, generate some of the demand for their services, so that even when there are large numbers of them per capita, they can keep their appointment books full. There is a growing consensus among health-care analysts that this perverse feature of medical economics is spurring a great deal of unnecessary care. And there’s a corollary: New physicians won’t necessarily go to (poor, rural) places that may need doctors. Many will go to affluent areas and places featuring a high “quality of life”—in other words, places already awash in physicians—where they’ll generate even more demand.
The second assumption underlying the push to train more doctors is that an increase can only lead to better health, so that as long as the market can support new physicians financially, we should create more of them. This idea also rests on shaky ground. A wealth of data suggests that health care is actually no better (and if anything, worse) in parts of the country, like Manhattan and Los Angeles, where we have very high numbers of doctors and, in particular, very high numbers of specialists. In a paper published last year in the journal Health Affairs, David Goodman and his colleagues at Dartmouth’s Center for the Evaluative Clinical Sciences examined care at academic medical centers—the hospitals that are associated with medical schools, considered the crème de la crème of American medicine. They tallied the number of doctors caring for Medicare recipients who were suffering from one or more chronic diseases and were in their last six months of life. The variation was enormous.