[A conceptual framework for good preventive practices (or for quaternary prevention)].

Prevention is universally advocated, especially in the case of noncommunicable diseases. However, given the proliferation of preventive technologies, it does not seem defensible to generically encourage preventive behaviors and tests for healthcare professionals and users. In this essay, we articulate concepts, ideas and criteria for considering preventive measures, providing a minimum guide to be used by professionals (especially in primary healthcare) and managers. The concepts of primary, secondary and quaternary prevention are explored, as well as those of reductive and additive prevention, high-risk and population-based preventive strategies; evidence-based medicine and its contemporary crisis; the precautionary principle; health promotion, an expanded, person-centered approach and shared decision-making. This discussion was designed to improve competence in the evaluation of preventive measures, making clinical and health decisions more judicious and less iatrogenic regarding primary and secondary prevention.