Researchers find that patients greatly overestimate the benefits and underestimate the harms of medical treatments and tests and say overutilization is largely a function of "poor judgment [and] subconscious biases" on the part of physicians.
Patients are dangerously clueless about the true value of many common medical interventions and physicians aren't doing enough to correct their misunderstandings.
That's according to a first-of-its kind meta-analysis of 36 studies, which ran last month in JAMA Internal Medicine.
Tammy Hoffmann, PhD |
"What surprised us was the consistency of the finding," says lead author and investigator Tammy Hoffmann, PhD, speaking from Bond University, Queensland, Australia, where she is on faculty. "Regardless of what treatment, test, or screening effort, or what country the study was done in, patients greatly overestimated benefits and greatly underestimated harms."
Chalk it up in part to physicians' true desire to "try something" for their patients, their limited exposure to shared decision making, poor explanatory skills, or their simple "pecuniary" desire to submit a claim, Hoffmann says. Misleading advertising from pharmaceutical companies and non-profit advocacy groups' exaggerated campaign claims share some of the blame, she adds.
Overdiagnosis, stemming from fee-for-service payment systems, and the knowledge that if clinicians don't do, they won't get paid, contribute to the problem, she says. "Plus, it takes more time to explain to a patient why something isn't needed compared to just writing the prescription or ordering the test. That's a huge driver."
Hoffmann and her team collected research papers that asked a total of 27,323 patients—about half in the United States—about their perceived benefits and/or their perceived harms from getting mammograms, prostate-specific antigen (PSA) and pap smear tests, mastectomies, and CT scans, to name a few.
The articles then compared what patients thought the interventions would accomplish, with actual, known rates of benefits and harms.
They were wrong most of the time.
'No Easy Answers'
For example on almost every study in which women were asked about mammography, they greatly overestimated its ability to either find a true cancer or prevent death. Men were greatly uninformed about the accuracy, benefits, and harms of PSA screening.
"It's a huge problem with no easy answers," says Hoffmann. "Patients are largely at the mercy of what the physician knows, and the onus is on him or her to be up to date. Some are, but others are not so skilled at keeping up."
Deborah Korenstein, MD, director of cancer clinical effectiveness at Memorial Sloan Kettering Cancer Center in New York, and author of an accompanying commentary, applauded Hoffmann's meta-analysis. "This is the first time I know of that anyone has put all this together to show a universal phenomenon," she says.
Hoffmann and Korenstein believe physicians should spend time with patients in a "shared decision-making" process, to make sure the patient understands, realistically, what to expect. And time should be spent explaining the chances that something could go wrong, even terribly wrong.
Korenstein attributes much of the problem to physicians' rusty math skills, or what she calls "poor numeracy."
"I've spent much of my career teaching doctors how to understand evidence, which they really don't understand that well," says Korenstein, formerly with the American College of Physicians. "So they end up having a very hard time explaining it to patients. For example, doctors and the public have a hard time understanding the difference between a therapy's relative benefit or harm with its absolute benefit or harm.
Societal Pressure Partly to Blame
Here's an example, Korenstein explains. "It sounds much nicer and cleaner to say to a patient, 'this is going to reduce your chance of having a heart attack by 30%.' But if the doctor says it another way, 'this intervention is going to reduce your chance of a heart attack from .1% to .07,' that's more accurate, but it doesn't sound so attractive."
Likewise for the controversial mammography screening initiatives in the United States and in Europe. Numerous studies have found that large numbers of women believe mammography saves countless lives from breast cancer. In fact, studies of a half a million women show the absolute risk reduction to be one woman's life saved for every 2,000 women who received recommended screening.
Direct-to-consumer advertising, especially in the United States, is a problem as well, Korenstein and Hoffmann say, because messages are geared to imply more benefit than can be reasonably achieved.
"This isn't an easy problem to fix, because people just assume that stuff works," says Korenstein, "because why else would we give it? That's a good question."
Sometimes doctors know better, but patients come in with a preconceived notion: They're set on getting a procedure or drug and they don't want to accept "no."
Hoffmann says some studies indicate that even though it makes doctors feel uncomfortable, many accede to their patients' requests for unnecessary care about half the time.
How much of it is just pure greed: Doctors performing unnecessary tests and procedures to submit claims and make more money?
Both Korenstein and Hoffmann acknowledge there's some of that.
But realistically, they say, overutilization is more a function of "poor judgment, subconscious biases, and the pressure in our society to always be doing more," says Korenstein. "That's what's driving this stuff."
A Potential Solution
One fix, and something both Korenstein and Hoffmann hope will come soon, is that the process of shared decision making becomes standard for every physician's encounter with a patient. First, it should be taught to every medical student. And then older practitioners should catch up.
Here's how it should work, Hoffmann says. "A parent whose child has a sore ear says, 'Doctor she needs antibiotics. Last time she got antibiotics she was better in two days."
Instead of writing the prescription, however, the doctor says "Ok. But we know from studies that three out of 100 children will get better, as opposed to two out of children will get better without antibiotics. And we know that five out of 100 who get antibiotics will get diarrhea and a rash. What if I give you the prescription, but you wait a few days to see if it gets better on its own before using it. How does that sound?"
Hoffmann says, however, "We still have a long way to go before that happens."