Highly educated and rigorously trained doctors may be just as susceptible to a built-in bias that bargain-seeking consumers yield to when they hit stores seeking 99 cent goods, buy into TV hype for $19.99 wares, or fall for a salesman’s pitch for a used car priced at $17,999.
Ivy League researchers call the cognitive flaw “left digit bias.” They warn that this common irrationality can have consequences with doctors and patient care.
As Anupam B. Jena of Harvard and Andrew R. Olenski of Columbia reported in the New York Times’ evidence-based column “The Upshot:”
“In a new study of physician treatment decisions, published … in The New England Journal of Medicine, we document signs of left-digit bias. This is the bias that explains why many goods are priced at $4.99 instead of $5, as consumers’ minds round down to the left-most digit of $4. We hypothesized that doctors may be overly sensitive to the left-most digit of a patient’s age when recommending treatment, and indeed, in cardiac surgery they appear to be. When comparing patients who had a heart attack in the weeks leading up to their 80th birthdays with those who’d recently had an 80th birthday, we found that physicians were significantly less likely to perform a coronary artery bypass surgery for the ‘older’ patients. The doctors might have perceived them to be ‘in their 80s’ rather than ‘in their 70s.’ This behavior seems to have translated into meaningful differences for patients. The slightly younger patients, more likely to undergo surgery, were less likely to die within 30 days. Our study confirms previous work that found doctors are overly responsive to patient age when diagnosing illness, and that showed how seemingly irrelevant factors‚ such as the difference of a few weeks of age, could govern physicians’ decisions about treatment, with potentially life-altering consequences for patients.”
The study emphasized — as Eric Boodman reported in Stat, the online medical and science news site — that doctors can be all too human, and they need to remind themselves of how biases may affect their patient treatment:
“It’s hardly surprising that doctors might make choices shaped by unconscious bias. We all do. We think memorable anecdotes are representative. We give too much credence to evidence that fits our beliefs and discount everything else. Those same fallacies, famously described by economist Daniel Kahneman and psychologist Amos Tversky, creep into the highly trained thinking of physicians, too.”
As Jena and Olenski wrote in the New York Times:
“Bias, which takes many forms, affects how doctors think and the treatment decisions they make. Racial biases in treatment decisions by physicians are well documented. One study found that black patients were significantly less likely than white patients to receive pain medication in the emergency department, despite reporting similar levels of pain. Other research suggests that longstanding racial biases among providers might have contributed to racial differences in patient trust in the health system.”
The researchers also noted:
“Unconscious biases can lead to disparate treatment of patients and can affect whether similar patients live or die. Sometimes these cognitive biases are simple overreactions to recent events, what psychologists term availability bias. One study found that when patients experienced an unlikely adverse side effect of a drug, their doctor was less likely to order that same drug for the next patient whose condition might call for it, even though the efficacy and appropriateness of the drug had not changed. A similar study found that when mothers giving birth experienced an adverse event, their obstetrician was more likely to switch delivery modes for the next patient (C-section vs. vaginal delivery), regardless of the appropriateness for that next patient. This cognitive bias resulted in both higher spending and worse outcomes. Doctor biases don’t affect treatment decisions alone; they can shape the profession as a whole. A recent study analyzed gender bias in surgeon referrals and found that when the patient of a female surgeon dies, the physician who made the referral to that surgeon sends fewer patients to all female surgeons in the future. The study found no such decline in referrals for male surgeons after a patient death.”
Indeed, patient safety advocates long have railed about how Big Pharma exploits physicians’ affinity and likability biases, allowing their prescribing habits to be swayed by the perceived collegiality they experience when a drug salesman buys them something as simple as a cheap pizza lunch. They also had high hopes that, with the advent of electronic patient records, doctors could be given “nudges” that would pop up onscreen to dissuade them from biases in treatment or prescribing. That recently has been shown to have gone wrong, with a software program that pushed the prescribing of powerful opioid painkillers in defiance of accepted medical recommendations. The software maker agreed to pay sizable federal penalties for failing to disclose that it had cut a marketing deal with an opioid maker to promote the drug.
In my practice, I see not only the harms that patients suffer while seeking medical services, but also how physicians’ too-human foibles contribute to the U.S. health care system’s significant problems with medical error, preventable hospital acquired illnesses and deaths, and misdiagnoses.
Doctors work long and hard to master their craft and they deserve credit for their properly applied diligence. But, as with all professions, medical practitioners may need to work hard to ensure they don’t outsmart themselves with inherent, human flaws. One review of medical literature found that “overconfidence, lower tolerance to risk, the anchoring effect, and information and availability biases” contributed to “diagnostic inaccuracies” in as many as 77% of case scenarios, and almost three-quarters of studies reviewed found “an association between cognitive biases and therapeutic or management errors.”
We may need to do more to help doctors heal themselves of their built-in biases, perhaps by listening to colleagues and patients more.