The impact factor as a phantom: Is there a self‐fulfilling prophecy effect of impact?

Can the journal impact factors regularly published in the Journal Citation Reports (JCR) be shaped by a self‐fulfilling prophecy? This question was investigated by reference to a journal for which incorrect impact factors had been published in the JCR for almost 20 years: Educational Research. In order to investigate whether the propagation of exaggerated impact factors had resulted in an increase in the actual impact of the journal, the correct impact factors were calculated. A self‐fulfilling prophecy effect was not observed. However, shows that the impact factors for Educational Research published in the JCR were based on calculations that erroneously included citations of a journal with a similar title, Educational Researcher, which is not included in the JCR. Concludes that published impact factors should be used with caution.