When doctors skip the numbers, patients may misjudge the health risks

When a physician says a procedure is “rarely risky,” what does that really mean?  Although terms like “common” and “unlikely” may sound descriptive enough, experts in medical decision-making suggest that leaving out numbers may be misleading for patients. 

In a paper published on April 29 in the Journal of General Internal Medicine, a team of researchers and clinicians explained that patients often overestimate risk estimates, like possible side effects or medical conditions, when given only verbal descriptions. They encourage doctors not to shy away from including numbers, offering a list of five science-backed tricks on how to make those numbers count. 

“One of the purposes of this paper is to help physicians figure out how to communicate numeric information about risks so that patients can understand and use them to make better choices, take charge of their health and be healthier long term,” said Ellen Peters, a professor at the University of Oregon School of Journalism and Communication and Department of Psychology. 

Peters, also director of the Center for Science Communication Research at the UO, draws on two decades of research on how patients understand numbers and make decisions. She said it’s a common concern that patients won’t understand numerical information, as about a third of American adults have limited numerical skills. 

 
But she’s found that people often prefer getting numbers. According to her previous studies, people rated messages more trustworthy and their messenger more expert when they provided data. 

In collaboration with physicians Paul K.J. Han of the National Cancer Institute and Clara N. Lee at the University of North Carolina, Peters hopes their recommended strategies will facilitate stronger shared decision-making between patients and their health care providers. 

“There’s a whole raft of strategies that you can use, some of which might be more appropriate in one situation versus the other,” she said. “But by choosing one of them, you can help people use statistics more than they typically would. Otherwise, numbers are just abstract and meaningless.” 

1. Communicate with numbers, not just words 

Physicians often default to verbal terms, knowing that a sizable portion of American adults struggle with simple numeric concepts, Peters said. But research has shown that people better understand risks and react appropriately when numbers are discussed alongside verbal descriptions. 

“When you present numeric evidence, like the likelihood of side effects for a prescription medication, what ends up happening is that it helps correct people’s original expectation,” Peters said. “They’re much less likely to overestimate the risk and are more likely to take on a physician’s recommendations.” 

Do: “Headache is a common side effect and occurs in 7 percent of people.” 

Don’t: “Headache is a common side effect.” 

1. Make numbers more manageable 

When patients are overwhelmed by medical information, they may rely on mental problem-solving techniques, like gut feelings, pre-existing beliefs and anecdotes they've heard from others. To avoid cognitive overload, Peters suggests limiting information to what’s important. If a disease has three intervention options but a patient has a condition that eliminates one as a viable option, she advises not to mention that option. 

The authors also suggest clinicians do the math for their patients. For example, they can calculate the risk of birth control based on the number of years the patient expects to use it instead of the annual risk. 

Do: Highlight only the key facts and tailor information to the patient’s situation. 

Don’t: Provide information that isn’t relevant to a specific patient. 

1. Provide context to statistics 

Numbers said alone can be meaningless, so Peters suggests using evaluative labels, like “a 6 percent risk is generally considered poor,” or comparisons to indicate whether it’s high or low risk. 

Do: “Ninety-three percent of patients survive with treatment A compared to 99 percent who survive with treatment B.”  

Don’t: “Ninety-three percent of patients survive with treatment A.” 

1. Acknowledge uncertainty 

Risk information is an estimate. In some cases, being upfront about the uncertainty of whether a patient will be a part of the 40 percent side or the 60 percent side of a risk, for example, can help convey to patients how seriously they should take it. 

Do: “Estimates of the chance of something happening are only a best guess based on the scientific knowledge we have right now. We do not know your personal real risk because of things about you that have never been studied and we don’t yet understand.”  

Don’t: Present numeric risk information as unerringly precise and correct. 

1. Test your communication through the teach-back technique 

Experts tend to overestimate how much other people know and how clearly they’ve communicated. So doctors can use the teach-back technique, Peters said, in which they ask their patient to repeat what they understood and found important. The physician can then insert more information to either correct what’s wrong or remind them of something. 

Do: “This can be hard to understand. I’d like to make sure I’ve explained it clearly. Could you tell me how you understand the pros and cons of taking drug X?” 

Don’t: “What questions do you have?” 

Such strategies also can be used by patients to advocate for themselves, Peters said. If told about a possible side effect, they can ask how statistically likely it is. If given too many possible side effects or treatments, they can request to simplify the information to the most important facts. 

Peters plans to conduct a series of studies to test which of the five strategies is the most effective. She also is interested in how storytelling and anecdotes affect patient decision-making. 

“Physicians have very limited time in any one appointment and are often faced with a similar patient over and over,” Peters said. “What that means is, if you’re trying to help them better communicate with patients, you’ve got to provide things that are fast and scripted so that everyone can make informed decisions about their care.”