The CiteScore journal metric is a numerical value that reflects the average number of citations referring to the articles published in a journal. This indicator was introduced in December 2016 by Elsevier as an alternative to the widely used Journal Impact Factor (JIF)calculated by Clarivate (the Web of Science database owner).
CiteScore calculation is similar to JIF, that is, it is based on the Scopus citation data. However, there are some differences. Thus, CiteScore considers the data over a 4 year- period rather than over 2 or 5 years, as is the case for the JIF.
Calculation method
The value changes from one year to another. So, for the reporting year Y, the СiteScore of a particular journal is equal to the ratio of the number of all citations received in the year Y, Y-1, Y-2, Y-3 by the articles of this journal published in the years Y, Y-1, Y-2, Y-3 to the total number of the articles. Thus, the publication window is four years [Y; Y–3] (the average citations number of this set of journal articles is thus estimated), the citation window is the same four years (citations made in the period considered are taken into account). The following types of publications are included in the CiteScore calculation: articles, reviews, conference proceedings, information documents, and book chapters.
The number of papers in the denominator makes it possible to compare journals of different size rather than only the absolute values of the citation numbers received. A journal with more papers published will be likely to receive more citations.
The compilers think that the 4-year CiteScore period provides a reliable estimate of post-publication citations. It is appropriate for all academic fields and long enough to capture the citation peak for most disciplines. The formula was updated in 2020, so all the previous values for 2016, 2017, 2018, etc. were recalculated. The image below is an example to clarify the above.
Scopus also predicts the CiteScores for the next year. This indicator is referred to as CiteScoreTracker and is updated every month. To calculate the CiteScoreTracker 2023 rating, the same methodology is used for citations. It is based on the latest data from 2023.
How to view a journal's CiteScore value and quartile
Compared to JIF, CiteScore is free and available even if you are not subscribed to Scopus. There is the Journal rankings section on the Scopus Preview page. There, you can find a paper by its title, subject area, publisher, or ISSN. The page also contains a filter for searching journals by quartile.
If you check the Source details, you can see the CiteScore indicator calculated. At the bottom of the page there is a detailed metric calculation including the numbers of papers considered and their citations. The CiteScoreTracker indicator is also given, which estimates the metric value for the following period. There is also the information about the journal's ranking and the particular percentile relative to the Scopus subject area where the journal belongs.
CiteScore vs Impact Factor
To summarize, the difference between the metrics is in the following:
- databases for calculation - Scopus for CiteScore and WoS for Impact Factor,
- accounting periods of papers and their citations,
- types of documents considered ,
- CiteScore values are publicly accessible, whereas IF is only available upon subscription to Journal Citation Reports (JCR).