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The 2021 Journal Citation Reports (JCR) with the Journal Impact Factors (JIFs) by Clarivate are now available. This year’s edition includes:

• more journals – content has been expanded to more than 20,000 journals from 113 countries and 254 research categories in the sciences, social sciences, arts and humanities.
• Journal Citation Indicator – a new field-normalized metric for journals across all disciplines.
• enhanced user experience – interactive visualizations, simpler navigation and contextual help make the JCR more intuitive to use.

Since Clarivate’s Journal Impact Factors (JIFs) are widely used (and often misused!), we want to highlight three common misconceptions about them in this blog post.

Misconception #1: The journal impact factor is a tool for scientists to evaluate the quality of the papers in a specific journal.

When the idea of the journal impact factor was originally conceived its primary goal was to give librarians a method to compare and select journals for acquisition into their holdings (Garfield, 1955). It was never designed as a tool to evaluate papers or individuals – especially not when it comes to making decisions regarding the allocation of research grants, hiring faculty members, or similar.

Misconception #2: The journal impact factor considers all publications and their citations for a specific journal.

Often it takes several years for a research topic to gain momentum and attract wider attention. The JIF however only considers the number of citations in a certain year and the “citable items” in that journal, which were published in the two preceding years:

While all the citations a journal receives in the given year count towards the JIF, not all publications of the two preceding years are considered citable items – only articles, reviews or proceedings. This can lead to an artificial inflation of JIFs – observed especially for journals like Nature and Science, which publish many widely cited editorials and news articles (Bornmann & Marx, 2016).

Misconception #3: The journal impact factor is a precise value.

In order to be able to sort journals by rank in the JCR, JIFs are given with three decimals and no confidence intervals or error bars. This data precision, however, is an illusion. The measurement of citation count is not an exact science as illustrated in bibliometrics on multiple occasions, e.g. Vanclay, 2012.

In conclusion, we advise you to consult several metrics and indicators in addition to the JIF to create a more complete evaluation of a journal. Examples for alternative journal metrics are:

• The Cited Half Life, which is the median age of the articles that were cited in the JCR year (included in Clarivate’s JCR)
• The 5-year impact factor (included in Clarivate’s JCR)
• The SCImago Journal Rank indicator  
• Citescore by Scopus
• The new Journal Citation Indicator (included in Clarivate’s JCR)

For an innovative citation metric on the article level you can try the Relative Citation Ratio via https://icite.od.nih.gov/

For a detailed guide and information on all the new features in this years JCR visit Clarivate’s Journal Citation Reports Help.