[Iatrogenesis. Individual error? System failure?].

Iatrogenesis has been considered for a long time as a situation created by the wrongdoing of an individual, that is, the physician. Nevertheless, we propose that medical error be considered a very complex "social omission" in which public funding, training of health professionals including administrators, and even the public education may be responsible for an adverse medical event, considering that medical officials are just a part of a system. Detection of latent errors and the epidemiologic study of those that have occurred, including differences in quality, must be considered as the main effort in prevention.