Impact Factor (English: impact factor), abbreviated as IF, is a data in the periodical citation report produced by Thomson Reuters. That is, the total number of cited papers published by a journal in the first two years of the reporting year (JCR year) divided by the total number of papers published by the journal in these two years. This is an internationally accepted periodical evaluation index.

Extended data:

During the period of 1998, Dr. eugene garfield, director of the American Institute of Science and Technology Information, described the generation process of influencing factors in the magazine Scientist. This shows that the purpose of his initial proposal of impact factors is to evaluate and select journals with current content.

Generally speaking, the impact factor refers to the citation data of journals in the world in the last year provided by 1975, Journal Citation Reports (JCR), and gives the impact factor of each journal included in the database. JCR is an authoritative comprehensive database in the world.

Its cited data come from more than 7,000 journals of more than 3,000 publishing institutions around the world. Professional scope includes science, technology and social science. JCR is the only comprehensive tool to evaluate periodicals in the world, because it is the only tool to collect the citation data of periodicals from all over the world. The JCR CD-ROM version has many good interfaces, showing the relationship between citation and cited.

It can tell people which journals are the most influential, which are the most commonly used and which are the most popular. In addition to the influencing factors, it also gives: current ranking, periodical abbreviation, and international uniform numbering (ISSN).