Evidence-based medicine and your health

In a conversation with Beth Nash, M.D. of the BMJ Publishing Group, publishers of the British Medical Journal, she outlines evidence-based medicine and how it could fit into your health care decision making.

We hear a lot about “evidence-based medicine” these days. Haven’t doctors’ decisions always been based on science?

Not always. Several cases in which research overturned longstanding practices that were just assumed to work pointed to the need for a formal, evidence-based approach. For example, for years it was believed that kids should have their tonsils removed to prevent recurrent sore throats.

But when it was properly studied, it turned out that it hurt more than it helped. A newer example is the use of estrogen replacement therapy to prevent heart disease in women after menopause. It made good sense in theory. Then the clinical trials came out and showed that it did more harm than good.

Isn’t it “cookbook medicine” to base decisions solely on research?

A treatment decision is like a three-legged stool. The first leg is the clinical evidence, the second is the doctor’s expertise, and the third is the patient’s values and preferences. Doctors need to integrate their clinical expertise and their years of experience treating patients, and you in particular, into their treatment recommendations. But at the same time, they should be receptive to questions about what the research shows.

Where do the patient’s values and preferences factor in?

Values could include religious beliefs, ethics, thoughts about living wills and advance directives, and so on. Preferences involve individual sensitivities. Some people are keen to avoid drug therapy, while others find it difficult to make lifestyle changes. Some prefer not to undergo surgery because of the potential risks. A good example of a condition where patient preference comes into play is prostate cancer, where the evidence provides no clear-cut idea of what intervention is best; surgery, radiation, and watchful waiting are all reasonable options. Women with breast cancer have similar decisions to make about mastectomy vs. lumpectomy or in some cases whether to have additional radiation or chemotherapy. You learn as much as you can about the available options, then follow your gut.