[Dialogue in Therapeutic Friendship: Statistics, Risk and Happiness].

It is almost universal to express the preventive or harmful health effects of a behavior or a medication as a percentage of variation between the starting situation and the one that considers this added factor. This figure of relative variation, isolated, does not allow us to take into account the relevance of said change, which may be quantitatively small. In the dissemination of health sciences, and especially in the dialogue with the patient, the basis of all preventive or therapeutic advice, relying on or using only this relative figure is misleading. When talking to the patient, he or she must be able to take into account the expected benefits or the risks he or she runs, without percentage reference to another situation, that is, the absolute advantages or dangers, so that a well-founded joint decision can be made. In this dialogue, issues related to the patient's ″lifestyle″ must appear, with due precautionary measures: omission of this can only prevent possible benefits for the patient.