Second principle of iatrogenics: it is not linear. I do not believe that we should take risks with near-healthy people; I also believe that we should take a lot, a lot more risks with those deemed in danger.

Why do we need to focus treatment on more serious cases, not marginal ones? Take this example showing nonlinearity. When hypertension is mild, say marginally higher than the zone accepted as “normotensive”, the chance of benefiting from the drug is close to 5.6% only one person in eighteen benefit from the treatment. But when tension is considered to be in the “high” or “severe” categories, the chance of benefiting are now 26% and 72%, respectively that is that one person in four and two persons out of 3 will benefit from the treatment. So the treatment benefits are convex to condition the benefits rise disproportionally, in an accelerated manner. But consider that the iatrogenics should be near-constant for all categories! In the very ill condition, the benefits are large relative to iatrogenics, in the borderline one, they are small. This means that we need to focus on high symptom conditions and ignore, I mean really ignore, other situations in which the patient is not very ill…

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