What is a good medical decision?
A good medical decision causes more good than harm. In other words its benefits-to-harms ratio leans towards the benefits.
For example, in case of infectious endocarditis, the benefits of antibiotic treatment clearly outweigh the harms of not receiving such a treatment, because without antibiotics death occurs sooner or later, whereas death caused by antibiotics is exceptional. Therefore all, or almost all, fully informed patients will choose to receive antibiotics under those circumstances.
What is a bad medical decision?
The benefits-to-harms ratio of a bad medical decision leans towards the harms (or the adverse effects). Let us note that "benefits-to-harms" ratio is more impartial than "benefits-to-risks" ratio. However health-care professionals often prefer to use the word "risk" rather than the word "harm": we shall come back to that further in our article.
For example, low fat diets (which provide less than 15% of calories derived from fat, and 70% derived from carbohydrates) have been promoted at the scale of whole populations, whereas the clinical benefits of such diets were never demonstrated, and the clinical harms, which were suspected even before those diets were promoted, are confirmed with the passage of time and the accumulating evidence. Let us note that this example, intended to illustrate the existence of bad medical decisions, does not mean the practitioners who promote such diets are malicious. These practitioners may be in good faith, as will be seen. Since a harm to come is less well proven than a present harm, it is more difficult to find current exemples, than ancient examples, of bad medical decisions.
Let us observe that only a minority of fully informed patients chose low fat diets, whereas all, or almost all, patients choose antibiotic therapy in case of infectious endocarditis.
Hence this preliminary proposal of general rule: a good (medical) decision would be the one favored by the overwhelming majority of patients.
Evidence, and judgments about this evidence, are the source of all medical decisions .
The evaluation of a benefit-to-harm ratio is often more complex than in our two examples, and it is generally difficult to be sure that a medical decision will be good or bad. The evaluation of a benefit-to-harm ratio is based, as we shall see below, not only on the evidence from biomedical research, or from the experience of the practitioner, but also on the value that the practitioner, or the patient, place on this evidence. This value can depend on our knowledge, our preferences, our beliefs, our prejudices: what determines us is not just evidence, but our judgment about that evidence.
1) The evidence:
Health-care professionnals generally claim that their decisions are based both on their experience and on quality evidence from biomedical research. This evidence is supposed to have been sought out and then analyzed systematically. Systematic reviews are the cornerstone of Evidence-Based Medicine [1].
Measuring a clinical benefit, or a clinical harm, is tainted with an uncertainty which can be important, and even very important, since:
– the quality of most studies (and therefore of evidence) which are currently available is suboptimal, including randomized trials. Especially since a large part of this evidence is produced by an industry whose raison d'être is more lucrative than philanthropic;
– research studies whose results are negative are less published than studies whose results are positive, which can bias, in an overly optimistic sense, our estimates of benefits-to-harm ratios. Especially since health-care professionnals tend to better evaluate benefits than harms. This trend is reflected in the use of the words "benefits/risks" in preference to the words "benefits/harms".
That is why the analysis of the quality of the available evidence, in order to estimate the benefit-to-harm ratio of a medical decision, is a complex task which allow less to learn a final “truth” than to estimate doubts, to quantify them in the best case. This complex analysis requires talent, impartiality and common sense. René Descartes (1596-1650) had observed it well: “Common sense is the most fairly distributed thing in the world, for each one thinks he is so well-endowed with it that even those who are hardest to satisfy in all other matters are not in the habit of desiring more of it than they already have” [2]. Blaise Pascal (1623-1662) summed up this idea well: “it is man's natural sickness to believe that he possesses the truth” [3].
2) The judgments:
In pure science, such as mathematics, a theorem becomes true as soon as it is proven. In medicine, the evidence do not allow to access such truths. Not only because biomedical evidence is not always of high quality, but also because each human being is unique: medical ethics would forbid us to apply truths to all. Every medical decision being able to bring both benefits and harms, such and such doctor, or patient, will attach more or less importance to such benefit, or to such harm, and will thus build their own benefit-to-harm ratio according to their own knowledge, preferences, beliefs, prejudices. In medical ethics, this is called patient (decision-making) autonomy.
For example, there are doctors who recommend to screen asymptomatic patients over the age of 50 for prostate cancer with annual PSA (prostatic specific antigen) blood test. They consider this practice allows earlier diagnosis of less advanced cancers, thus allowing less aggressive treatments. Other doctors advise against such a screening and put the emphasis on: 1) the lack of a clearly proven effect of sreening on overall mortality (the quality of randomized trials is not high enough to demonstrate, or to refute, such a benefit); 2) the false positive, that is elevated PSA without cancer, causing unnecessary, or even harmful, explorations, especially since such screening is aimed at asymptomatic patients; 3) and especially the over-diagnosis (that is the discovery of cancers, which, in the absence of screening, would never have led to a disease) with a heavy morbidity of the curative treatments (incontinence and impotence).
In this example, based on the same evidence, different professionnals or patients end up, using their common sense, making diametrically opposed judgments, or decisions. This again proves Descartes or Pascal right, who observed that we come to our beliefs less by the evidence than by the attraction of our beliefs on us. These mathematicians and philosophers also observed that we are generally the better persuaded by the reasons we discover ourselves than by those given to us by others. We also know that we should almost never trust our first thoughts as our second thoughts use to be sharper than the first ones.
The individual and the human community, or how to understand equity ?
As we have seen, a decision will be deemed relevant by a given practioner, and a given patients, as long as this decision will have provided maximum benefits to the patient, and minimal deleterious effects. Medical ethics prefer the words beneficence and non-maleficence, which are fairer than the words benefits and riks. More deeply, medical ethics considers at least two other core principles: patients autonomy, as mentioned in our various examples above, and equity, which we have yet to address [4].
Equity (or justice) is a virtue which consists in regulating one's conduct on the natural feeling of the just and the unjust. In our example of prostate cancer screening, is it fair to spend huge resources worldwide, to achieve a weakly positive, or even doubtful, benefit-to-harm ratio, whereas the same resources could avoid greater misfortunes, for example to provide access to drinking water to populations who are deprived of it?
Autonomy mainly concerns the individual. Equity mainly concerns the human community. Both the individual, and the community, can be selfish. But if our selfishness were watching over us just to keep us safe from mistakes and vices, then wouldn't our selfishness be a virtue [5]? Doesn't our heart tell us that such a virtue is more within the reach of the entire human community than of an isolated individual? Maybe Blaise Pascal was thinking about such questions when he wrote that the heart has its reasons that reason ignores and that almost all of the misfortunes of life come from the misconceptions we have about what happens to us. For example, it our our heart, not our reason, that tells us that God exists, especially when this God is the one presented to us by Baruch Spinoza [6].
Blaise Pascal had also understood that error is not the opposite of truth, but the forgetting of the opposite truth. Niels Bohr (1885-1962), one of the inventors of quantum physics, expresses this paradox thus: the opposite of a simple fact is falsehood, but the opposite of one profound truth may very well be another profound truth [7]. Regarding, for example, worldwide population containment during the spring of 2020, both these two statements are, during spring 2020, as true as the other:
- our containment will have many negative consequences: it would have been better not to decree it,
- our containment will have many positive consequences: those who decreed it must be thanked.
Hence this final proposal of general rule, less individual than the previous proposition: a good (medical) decision would be the one that, for a given investment, would bring the greatest possible beneficence to an entire population.
References:
[1] Sackett DL, Straus SE, Richardson SW, Rosenberg W, Haynes RB. Evidence-Based Medicine: How to Practice and Teach EBM. London: Churchill Livingstone; 2000.
[2] René Descartes Le Discours de la Méthode. Pour bien conduire sa raison, et chercher la vérité dans les sciences. Leyde, Juin 1637.
[3] Blaise Pascal. Les Provinciales. Lettres écrites par Louis de Montalte à un provincial de ses amis et aux RR. PP. Jésuites sur le sujet de la morale et de la politique de ces Pères. Cologne, Mars 1657.
[4] Joseph Watine. What sort of bioethical values are the evidence-based medicine and the GRADE approaches willing to deal with? Journal of Medical Ethics 2011; 37: 184-6. doi: 10.1136/jme.2010.039735.
[5] Alain. Les Arts et les Dieux. Editions Gallimard, Dijon, Janvier 1958.
[6] Baruch Spinoza. Ethica Ordine Geometrico Demonstrata. Editionis posthumae, 1667.
[7] Niels Bohr, as quoted in "Niels Bohr: His Life and Work as Seen by His Friends and Colleagues" (1967).
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The French translation of this article can be read here:
https://blogs.mediapart.fr/wawa/blog/210320/quest-ce-quune-bonne-decision-medicale
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