Today, the Clarivate Analytics (formerly ISI) Impact Factor is an established measurement of quality — but how did it become so? How was it developed and how can it best be used?

In September 2005, Dr. Eugene Garfield presented a paper, “The Agony and the Ecstasy — The History and the Meaning of the Journal Impact Factor”, that addresses this topic, at the Fifth International Congress on Peer Review in Biomedical Publication, in Chicago, USA.

In the paper, Garfield discusses how he and Dr. Irving H. Sher came up with the journal impact factor, its proper and improper uses, citation analysis, scientometrics, journalology, and webometrics. He illustrates how Journal Citation Reports uses the impact factor to rank journals by impact factor, and includes a wide variety of examples of citation analysis.

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