The evaluation of the efficacy and safety of a clinical tool, be it a diagnostic technique, a preventive methodology, or a therapeutic intervention, is an im portant responsibility of physicians. The history of medicine is characterized by the authoritarianisms of teachers and of organizations giving way to the clinical experience of physicians; authoritarian dictum was replaced by case report and then by case series. As physicians learned to substitute the analysis of data for the inconsistencies of dictums and anecdotes, the problems of the case series as an investigative tool became more...