A blog from the Centre for Research Ethics & Bioethics (CRB)

On “truly” understanding the risk

Pär SegerdahlIt is a well-known psychological fact that people have great difficulties to understand probabilistic risks. What does it actually mean that the risk of developing breast cancer the next ten years is fifteen percent? In addition to the difficulties of understanding probabilities, mathematical expressions can cause a false appearance of exactitude and objectivity. It is often about uncertain evaluations, but expressed in seemingly definitive figures.

At our Monday seminar, Ulrik Kihlbom discussed another difficulty with understanding risk information. It can be difficult to understand not only the probabilities, but also what it is you risk experiencing. Sometimes, people face enormously complex choices, where the risks are high, but also the benefits. Perhaps you suffer from a serious disease from which you will die. However, there is a treatment, and it may work. It is just that the treatment has such severe side effects that you may die even from the treatment.

Ulrik Kihlbom interviewed physicians treating patients with leukemia. The doctors stated that patients often do not understand the risks of the treatment they are offered. The difficulty is not so much about understanding the risk of dying from the treatment. The patients understand that risk. However, the doctors said, no one who has not actually seen the side effects understand that the treatment can make you so incredibly ill.

Yet, it seems like quite comprehensible side effects: fatigue, serious infections, nausea and vomiting, stomach cramp, diarrhea, skin irritation, pain, and weight loss. Why would patients find it difficult to understand these risks?

Could it be that doctors have too high demands on “real” understanding? Must the patient, in order to “truly” understand the side effects, already have experienced the treatment? According to the doctors, experienced patients are at least easier to inform about the side effects. At the same time, the requirement that one must have had the experiences to really understand them seems too strong.

Rather, says Ulrik Kihlbom, doctors probably notice from the patients’ attitude that some of them underestimate what it is like to experience the side effects. Such attitudes can be sensed. The patients understand verbally that they are at risk of these side effects, but emotionally they do not really understand what the side effects are like, especially when they come together for a long time.

This resembles a general human difficulty. We often neglect how we ourselves are affected by our experiences. We project our present, unaffected self, and think: “I’m strong, I can handle those side effects.” However, when we actually experience the side effects, we are no longer strong! The self is not a constant, but changes with our experiences.

Here, then, it is not the probabilities that cause the difficulties, but the words. We understand the side effects verbally and can easily reproduce them. However, even words can cause a false appearance of objectivity: as if the experiences the words denote would not really reach us at our core. We separate ourselves from what we verbally understand we may experience, as if we could live our lives without being affected… without actually living them.

Ulrik Kihlbom has found a striking example of yet another aspect of the difficulty of understanding risk information. Not only probabilities but also common words such as “nausea” can create characteristic misunderstandings of risk information.

Pär Segerdahl

This post in Swedish

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  1. keithnoback

    In the climbing world we speak of subjective and objective hazards.
    Subjective hazards are things like tying your knot incorrectly or stepping on a hold that will not support your subsequent movement.
    Objective hazards are things like avalanches or holds breaking.
    Because we can have some insight into the conditions under which objective hazards exist, we can often convince ourselves that objective hazards are really subjective hazards.
    The misapprehension happens almost automatically when motives all line up in the right direction.
    Perhaps a similar process is at work in both parties when the risk/ benefit conversation happens. Patients may convince themselves that they are in charge of things which will in fact, just happen to them.
    On the other side, a physician constantly works to escape his/ her agency in treatment harms, yet we propose harms in any treatment and simply hope for the best, like the person we treat.

    • Pär Segerdahl

      Thank you for this excellent remark, which I think was profound. It was to begin with very interesting as an observation about climbing. But one senses also that it has the general significance that you indicate. I can imagine that you are right, a similar process may be at work in the conversation between physician and patient. Perhaps it is even encouraged in the ideal of the fully informed, autonomous decision maker. So many of us want to be in total control over our lives. I believe I will often have reason to recollect your description of climbing!

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