What is the biggest mistake patients make?

The biggest mistake patients make isn’t what you think. It isn’t turning down tests or treatments their doctors recommend. Nor is it deciding not to take the medicines their doctors prescribe. It isn’t insisting on getting a test or beginning a treatment their doctors recommend against, either, and it isn’t failing to exercise, stay out of the sun (or use sunscreen), quit smoking, or lose weight. No, the biggest mistake patients make is thinking anecdotally rather than statistically.

We all tend to arrive at our beliefs about the frequency with which things occur not from statistical analysis but from the ease with which we can recall examples of their happening (see Daniel Kahneman’s book, Thinking, Fast and Slow). So if we’ve recently heard a story of an airplane crash in the news, we’ll believe the likelihood that the airplane in which we’re flying might crash to be greater than it actually is. Or if a friend tells us about a complication he suffered following surgery, we’ll believe the likelihood of that complication happening after our surgery to be greater than statistics suggest.

We all tend to believe stories more than facts. And when faced with the need to make a decision—to start a medication, to have surgery—far more often than not (and mostly without consciously realizing it) we rely on our emotional beliefs about the risks and benefits. And our emotional beliefs come mostly from our experience and the stories we tell ourselves about it. “My wife’s sister’s boyfriend took that pill and had a terrible reaction. There’s no way I’m going to take it!” one patient tells me. “Dr. X operated on a friend of mine and he’s been in pain ever since. No way I’m letting that guy touch me!” says another. “I’ve seen that drug advertised on television. What do you think about me trying that one instead?” a third asks.

We believe thinking this way leads us to make wise decisions, but it doesn’t. We hear about a friend or relative having a known complication as a result of a surgery (one we’re told by more than one doctor that we need ourselves) and decide as a result of hearing that story that we don’t want the surgery—even though the statistical likelihood of such a complication happening to us is less than one percent and has, in fact, never happened to any of our own surgeon’s patients. Or we read about the side effects of a drug our doctor recommends and decide we don’t want to take it even though studies show that the risk of those complications is far lower than the likelihood that it will treat our symptoms or even prolong our life.

Sometimes our intuition actually serves us well. Sometimes the recommendations doctors make are based on nothing more than their clinical judgment and a presumption that they know better than their patients what their patients should do. And while the former is unavoidable (much of what we do in medicine requires judgment because studies that provide clear-cut answers haven’t been done) the latter represents a mistake that often leads doctors to have greater faith in the value of their recommendations than is warranted. But just because we may disagree that our doctor knows what’s best for us, we shouldn’t automatically dismiss his advice if it runs counter to our inclinations, for doctors have a crucial advantage over the patients for whom they care: the ability to think dispassionately about the choices their patients must face.

I’m not advocating that you surrender your judgment to your doctor. I’m saying that when deciding upon the best course of action to take, you need to critique your own thought process mercilessly. Most of us make our decisions emotionally. And while bringing emotion into decision making isn’t wrong per se (how do we place value on something, after all, if not with our hearts?), our feelings can easily mislead us if not based on sound reasoning. And allowing our fears to be swayed by anecdotes rather than statistics is about as far away from sound reasoning you can get.

To think statistically is to calculate the true likelihood that something bad—or good—will happen to us. And in far more cases than most would believe, we have information that allows us to do so accurately—and not only in the medical arena. We know, for example, that the likelihood of any one of us becoming the victim of a terrorist attack is about one in twenty million. But think: is your fear of terrorism proportional to that statistic or to the frequency with which you hear about terrorism almost weekly on the news? Another example: you should be far more afraid of driving a car than flying in an airplane. Not only are car accidents statistically more likely than airplane crashes, but also most of us drive far more often than we fly, thereby exposing ourselves to the risk of a car accident far more often than we expose ourselves to the risk of an airplane crash. But how often do you worry about getting in an accident when you take your car?

I’m not suggesting you need to; in fact, I’m arguing the opposite: that because of our exposure to anecdotes, we often worry far more than we should about things whose statistical likelihood is actually small (and, conversely, not enough about things whose statistical likelihood is actually large). So the next time you contemplate refusing a recommended test or treatment, notice the source of your anxiety: is it from a calculated statistic that yields the true likelihood of harm—or from a story that stirs you up far out of proportion to the real risk?

Alex Lickerman is an internal medicine physician at the University of Chicago who blogs at Happiness in this World.  He is the author of The Undefeated Mind: On the Science of Constructing an Indestructible Self.

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  • Anthony D

    I say its when they skip appointments and not taking your medications correctly.

    That’s my thoughts!

  • Suzi Q 38

    No excuse for skipping appointments, but empathize with the fact that the package inserts of most prescription are scary.

  • ofps

    In my view a bigger mistake can be putting too much confidence in a doctor who puts more stock in statistics than in the patient before him/her. We’re not lab values or statistics, we’re your patients and we are all different!

  • gillianp

    As a student of Narrative Medicine I hope that patients continue to tell and value their own stories and that their physicians listen very carefully to them. Statistical averaging is a very recent development in human history. Check out the article by UK scholar Jeffrey Aronson in which he says that pushing anecdotal evidence to the bottom of the evidence hierarchy skews statistics. “Unity from Diversity: The Evidential Use of Anecdotal Reports of Adverse Drug Reactions and Interactions” (Journal of Evaluation in Clinical Practice, 11, 2, 195-208)

  • Ren

    Statistics can be manipulated to fit anyone’s opinion or agenda. Meanwhile, anecdotal evidence is human and intensely personal, and should be listened to without question. The human perspective is always more important than the statistical perspective.

    • T H

      While anecdotes certainly makes people feel like they are making a better choice, it is rarely good medicine, especially when it goes against evidence-based medicine. Most humans make intuitive decisions and look for the evidence to support that decision rather than looking at the evidence and then making a decision. Anecdotes feed into this.

      • ofps

        Seems to me that for patient-centered medicine, the patients themselves should count as evidence.

        • T H

          They do.

          My job is to look at the patient as a whole person, not just as ‘thyroid disorder with osteoporosis.’

  • T H

    The biggest problem with statistics is that most people don’t have the knowledge to know what they actually mean. The difference between relative risk, odd-ratios, NNT, etc… It takes time and effort to understand (or to even have a feel for) what these mean. The disconnect between medical training and layperson training is at its greatest when statistics are brought into the equation.

    • ofps

      Tell that to any thyroid patient whose doctor declares that because their levels are now “in the range” their ongoing symptoms must be from something else. No matter that the ranges are broad and the symptomatic patient might feel much better in another part of the range. Sigh. Absolute focus on numbers and statistics is no good for anyone. And patients see it too often today, reporting that their doctors don’t even want to hear about how they’re feeling, only looking at their levels.

      • T H

        Thank you for making my point for me: you’re talking lab values and I’m talking statistics. Apples, oranges.

        And who’s talking about absolute focus? I never said a thing about it.

        Consider this: what if the ongoing symptoms ARE from something else? Should we not look for those because your friend, mother, random church acquaintance thinks that ‘oh, it’s obviously your thyroid’ ?

        I’m not doing my job if I don’t consider other etiologies of your ongoing symptoms.

        • ofps

          I see, so lab reference ranges aren’t statistical?

          And which statistics are going to guide your care of the patient who comes in with a basketfull of hypothyroid symptoms, a high-normal TSH, low normal FT4 and elevated antibodies? And a family history of Hashimoto’s.

          I see patients report very frequently that in a situation like that, their doctors do not suggest a trial of thyroid meds. That is over-reliance on labs and statistics imo. And ignoring the patient in front of them.

          And it happens all the time. Maybe not with you…….hopefully not with you.

    • http://warmsocks.wordpress.com/ WarmSocks

      The biggest problem with statistics is that most physicians don’t remember (if they ever learned) that statistics apply to groups, not to individuals.

  • Suzi Q 38

    Another anecdotal story from “the web:”

    “I will say that I was 37 when I began having angina, and even though I knew what the classic signs were, and I had them, I was of course in some kind of denial that I really had anything that couldn’t be controlled by meds only. So I was not completely surprised when I got up the courage to have a family member take me to the ER after Easter dinner, and a medical resident with big blue eyes told me he thought this was indigestion, and he would be discharging me with some antacids, etc.

    Like the others I have to say I was lucky that a senior ER doctor came in to see me at the last minute, listened to my symptoms and said if he closed his eyes and imagined I was 30 years older, he would believe this was my heart, so he kept me overnight. I did a stress test in the morning and was rushed in to the cath lab, had multiple blockages in LAD, one over 90%, multiple stents.

    Now, in the later years what some have said to me in my search for diagnosis for my other illnesses, those are some other stories.”

    Anything can happen. It depends on who you get to treat you. Even the best doctors can make an error. The body is huge and so much can go wrong and go right.

  • meyati

    I’m not a statistic, I am a person. Before a doctor looks at the stats, and makes his bet, I’d like them to listen to me- to give me almost as much attention for 60 seconds that they’d give their fantasy football team. Why should a doctor listen to ‘yap’. My temp is 96, so I complain of a fever when my temp is 97 or 98. The HMO now has these new temp machines that don’t register temps below 98. When I was hospitalized for a wound infection, they ended up doing an oral. Good doctors will place their hand on the back of my neck, and have said that they never imagined that a person could be burning up at 97 degrees. I wish that my HMO would send all of those machines back and get something reliable. Things like these machines are part of the uncontrollable medical costs. Nobody is responsible for anything. No administrator wants to admit they made a mistake.
    Probably the stats on body temps like that would cause a doctor to think that I’m confabulating. A physician-especially one with a sloppy nurse, ends up having more problems with me. I get released from hospitals because they think that my temp isn’t high. Then I need more care to kill the infection, or I keep going back until my glands are grossly swollen whatever.

  • disqus_cTYPCkCVDM

    After 32 years in practice I am convinced more and more how individualised and unique our pathological response to both typical and atypical illness can be – soft neurology being the best example. To extrapolate rigid diagnostic criteria to individuals is fraught with danger and is often disrespectful to our patients The satisfaction in practising intelligent medicine is in fact to think laterally and to wonder why something happens rather than simply ‘that is how Harrison says it is’.
    While we treat individuals with a unique constellation of often co-morbid symptomatology in primary care we also have the privilege and luxury of being able to accept uncertainty and to think somewhat more laterally than those unfortunate clinicians in the non-primary care specialities.