As much as we'd like to believe that medicine is exact, it often seems unpredictable, more a method of trial and error than precision. The care you receive can depend on what doctor you see, what health plan you use--and even something as arbitrary as your ZIP code.
If you live in Wyoming, for instance, you're five times more likely to have back surgery than if you lived in Hawaii. In Nebraska, you're more than twice as likely to have a knee replaced than in New Jersey. And if you're a woman diagnosed with breast cancer in South Dakota, you're nearly seven times more likely to have a mastectomy than if you lived in Vermont.
Well-informed patients should know about these geographic discrepancies, reported in a 2006 analysis by Dartmouth Medical School researchers, if only to grasp the tremendous variation in treatments recommended by American doctors. And, as patients are asked to take on more and more responsibility when it comes to making (and paying for) health care choices, it's important they understand that there's often little or no scientific evidence they will be better off undergoing expensive, invasive treatments. In fact, sometimes these cures do more harm than good.
'A lot of what's done is not based on good evidence,' says Dr. David Hahn, a family physician at the Dean Medical Center in Madison, Wisconsin, 'and a lot of physicians don't know that what they're doing isn't based on good evidence.'
Enter the evidence-based medicine movement, a concept that originated about two decades ago but has gained momentum in recent years as our overburdened health care system has floundered. The idea is to base clinical decisions on statistically and scientifically sound evidence, rather than on individual doctors' intuition or judgment--which has raised hackles among those who tend to value their judgment and intuition.
It's not that doctors are doing a bad job, proponents of evidence-based medicine say; it's that they often don't realize that their treatment choices are based less on evidence and more on their training, the philosophy of their practice, or their anecdotal experiences. To remedy these biases, evidence-based medicine looks to the 'gold standard' of research: the randomized controlled trial, which uses groups of randomly assigned study participants to compare the efficacy of different treatment approaches.
For example, many people with clogged arteries who aren't in immediate danger of having a heart attack have been routinely treated with an angioplasty and the insertion of a stent to expand the artery. It had been widely assumed that the stent would help keep the artery open and improve the person's prognosis. But in March, results from a five-year clinical trial of nearly 2,300 people showed that those who underwent the angioplasties with stents did not have better long-term results than those who were treated solely with medication. They didn't live longer or suffer fewer heart attacks.
Such studies offer guidance for people weighing treatment options, but they also point toward fixes for our ailing health care system. Hahn calls evidence-based medicine one potential tool to create 'value' for patients by balancing costs with high-quality health care. This value, he says, is 'the only thing that's going to save patients from harm, and save our health care system from bankruptcy.'
To improve individual health as well as the health of the system, researchers at the Dartmouth Atlas of Health Care analyze the use of medical resources throughout the United States by culling data on Medicare beneficiaries (which is considered a fairly accurate predictor of health care usage by those under 65 as well). That's how they found the tremendous geographic discrepancies in such high-cost procedures as mastectomies and back surgeries--variations that also contribute to big dollar discrepancies.
The atlas shows that health care for the average Medicare recipient in 2003 cost $11,352 in Miami and $7,783 in Detroit, but only $5,213 in Minneapolis.
'The system rewards high-cost procedures that have no benefit, that patients don't want, or, in fact, are harmful,' says Dr. Elliott Fisher, professor of medicine at Dartmouth Medical School and one of the directors of the atlas project.
While people may sometimes benefit just as much from medicinal therapy, lifestyle changes like diet and exercise, or even just waiting to see if a condition improves over time, doctors aren't reimbursed for talking to people about those options or helping them live comfortably with symptoms.
'We need to step back and ask, 'Is what we're doing really working?' That's the answer to some of our health care cost problems,' says Dr. Doug Campos-Outcalt, associate chair for family and community medicine at the University of Arizona. 'A lot of people are getting treatment they don't need, and a lot of people are making money on it.'
Critics contend that evidence-based medicine is too constricting, that it limits the evidence doctors can use to make their recommendations, ignores their experience and intuition, and discounts the 'art' of medicine. Worse, they warn, it could potentially tie physicians' hands when it comes to pursuing a wide range of treatment options.
'By anointing only a small sliver of research as best evidence and discarding or devaluing physician judgment and more than 90 percent of the medical literature, patients are forced into a one-size-fits-all straitjacket,' wrote Dr. Bernadine Healy, former director of the National Institutes of Health, in a U.S. News & World Report column (Sept. 11, 2006).
Proponents respond by stressing that the movement isn't out to force doctors to only look at randomized controlled trials--which aren't always an option when it comes to testing certain treatments--but rather to encourage them to examine the available evidence and use it to make the best judgment possible.
'Some people act like having evidence is a tyranny that tells you what you've got to do,' says Floyd J. Fowler Jr., president of the Boston-based Foundation for Informed Medical Decision Making. 'Common sense and clinical judgment are not always right. You don't want to forget about thoughtful, informed opinion. But thoughtful, informed opinion buttressed by evidence is better.'
The reality is that most medicine doesn't have strong evidence proving categorically that one treatment is better than another. Having more evidence and better evidence is simply a starting point to help us understand what's likely to work and what isn't.
'From a patient point of view, it can only be good to have evidence about effects of treatments,' Fowler says. 'There is no downside.'
Consider the mastectomy example from the Dartmouth atlas, which found that 2 women per 1,000 female Medicare recipients have mastectomies in South Dakota, compared to 0.3 per 1,000 in Vermont--despite the fact that that there are few differences in long-term outcomes for women who have mastectomies and those who have less invasive lumpectomies followed by radiation.
But when women are diagnosed with breast cancer, some may choose the more radical mastectomy. They may want to get rid of the breast to minimize any chance of recurrence. Others may want nothing more than to save the breast and opt for the lumpectomy.
'Folks just have different perspectives,' Fowler says. What's important is that people make decisions that factor in both the potential success of a treatment and the possible side effects or loss of quality of life. And that means learning to ask about the evidence. 'Patients,' Fowler says, 'shouldn't delegate important decisions to doctors without being informed.'