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Faculty Publishing Resources

What is the Impact Factor?


What is the Impact Factor?

The impact factor was created by the company Thomson Reuters. It is the oldest and best-known measure of journal metrics. 

The impact factor measures how often the articles in scholarly journals are cited. Journals with high impactor factors are usually considered prestigious

Pepperdine does not subscribe to the Journal Citation Reports (JCR) database from Thomson Reuters, but it is important to remember that Thomson's impact factor is only one of several instruments for ranking the prestige of journals. 

How can journal prestige metrics help faculty authors?

  • You can avoid predatory journals by using SCIMago and JCR because these databases generally only contain legitimate journals.
  • SCIMago and the JCR are helpful for identifying suitable journals for publications

  • While citations to your articles is based on many factors, authors publishing in highly ranked journals are more likely to obtain more citations to their works.

How can journal rankings be misused?

  • Impact factors and the SCIMago Journal Rank refer to the prestige of the journal not the author or their individual articles
  • Faculty applying for tenure or promotion should not be judged solely on journal prestige. It's important to also consider article level metrics such as how many times an authors' works were cited.

Oct. 2016 -- Thomson Reuters was acquired by Onex Corporation and Baring Private Equity Asia the company is renamed Clarivate Analytics

1988 Thomson Reuters acquired the Institute for Scientific Information (ISI)

SCImago Journal & Country Rankings


Rankings are based on the number of times articles within a journal are cited and the prestige of the journals where the citations appeared.

.The journals in SCIMago are drawn from the library's Scopus database.

Currently, there are about 32,000 journals indexed SCIMago while the Journal Citation Report database from Clariviate (publishes the impact factor only indexes 12,000 journals


CiteScore from Elseiver

CiteScore from Elsevier

CitesScore from Elsevier is new freely available resource that ranks and evaluates over 22,000 journals based on how often their articles are cited by other journals. Here are some issues with this new metric:

  • Doesn’t always correlate with Clarivate Analytics (formerly Thomson Reuters) Impact Factor

  • Counts *all* document types such as letters and editorials

  • Elsevier, the company responsible for CiteScore, also publishes journals

  • CiteScore evaluates almost twice as many journals as Clarivate Analytics (Thomson Reuters) Impact Factor

  • Updated monthly (most journal ranking resources are updated annually)