[Good and bad uses of the Impact Factor, a bibliometric tool].

The Impact Factor (IF) is a bibliometric tool that has become very popular among the academic people. It has been developed by the publishers of scientific reviews to determine the impact of their journal among the scientific and medical community. It is based on the following principle: more often are cited the articles of a journal, more often is that journal read and thus sold. Various secondary applications have been performed with the IF, including the evaluation of the academic curriculum of a scientist or of a research group. That approach is however not validated, a recent methodological study having demonstrated a lack of good correlation between the IF of a given review and the quality scores of its published articles.