Our paper presents an overview on the role of impact factor (IF) in the valuation of the scientific activity. With maximal objectivity based on published articles the perspectives are outlined and the role of specialized medical journals like Journal of Czech Physicians is shown. When IF is used for evaluation, the full English term should be first considered “journal impact factor“. It expresses the bibliometric features of the given journal, without possibility to transfer this assessment to individual articles or even authors. IF determined on the basis of information from citation indexes represents for an article presented in the journal the probability to be cited. It appears to be evident that this valuable parameter can lead in hands of inexperienced or irresponsible evaluator to incorrect and erroneous conclusions or to be misused. It is useful neither for evaluation of publication or scientific activity of an individual nor for the comparison of journals in different scientific disciplines. Owing to the relation of IF to the probability of an article to be cited, IF reflects the features (quality) of an article which brought the citation. IF is therefore determined also by the activity of scientific editors and referees. IF becomes part of everything what is related to the publication of scientific results and therefore it becomes object of journalogy. It is the source of meritorious intentions of the editorial board of Journal of Czech Physicians to deal with this phenomenon.

        Key words: impact factor, citation registers, bibliometric indicators, evaluation of publication activity, evaluation of the research, E. Garfield.