Harm vs. Benefits

The world of health care has changed dramatically since the days of “doctor knows best” — in recent decades, the typical relationship between a doctor and a patient has become less hierarchical and more collaborative, with patients encouraged and expected to take an active role in their care. At the same time, the proliferation of new treatments for many health conditions means that patients have more options — and, thanks to the Internet, more information — than ever before. As a result, many people are less inclined to follow the advice of any single doctor — but may still believe that the health-care system holds the answers to whatever ails them.

One consequence of widespread trust in medicine is that many people discount the risks, and believe too strongly in the benefits, of medical treatments. While some scientists have long known this to be true based on smaller studies, not until recently did researchers attempt to review all existing studies on this subject to see if there was a pattern across time and among different medical treatments. The resulting review, published in the February issue of the journal JAMA Internal Medicine, looked at 34 different health outcomes that patients were asked to evaluate in 32 different studies. In 22 of these 34 studies, or 65%, the majority of patients surveyed overestimated the benefits of the medical treatment they were being asked about.

Advertisement

For example, as noted in a New York Times article on the review, a 2002 study asked women who had undergone a double mastectomy (breast removal) to estimate how much the procedure had reduced their risk of breast cancer. On average, the women believed they had reduced their cancer risk by 65 percentage points, from 76% to 11%. In reality, for the 80% of the women in the study without a genetic mutation that dramatically raises breast cancer risk, the risk of developing cancer before their mastectomy was about 17%. In another study, 94% of patients overestimated the benefits of bowel cancer screening, with the largest number of respondents (33%) answering that for every 5,000 people screened over 10 years, 1,000 bowel cancer deaths could be avoided. Another 25% of participants said that 500 deaths could be avoided as a result, while 21% said that 100 deaths could be avoided and 15% said that 50 deaths could be avoided. In reality, 5 deaths would be expected to be avoided, a number than only 4% of patients selected (another 2% said they didn’t know).

As the Times article notes, this study lends support to the idea that if patients were given more detailed information about the benefits and risks of medical treatments, many of them might opt not to be treated in some cases. Doctors, understandably, tend to focus on the potential benefits of procedures more than the risks, and patients may also be swayed by the idea that it’s best to “do something” rather than nothing. However, there is some evidence that many chronic condition, such as diabetes, are undertreated. If more patients knew their likelihood of developing diabetes complications, it’s possible that they would opt for a more aggressive treatment strategy than many do right now.

Has your health-care team told you about the risks and benefits of treatments you’ve considered receiving? If so, do you feel this was part of the decision-making process for you, or was it just an afterthought? Do you feel able to weigh the benefits against the potential harms of a procedure, or would you rather leave that process to a doctor or other health-care professional? Do you think doctors can be expected to soberly consider the risks of treatments that they perform or prescribe? Leave a comment below!