Thomson Reuters Statement Regarding the San Francisco Declaration
on Research Assessment

Thomson Reuters acknowledges the efforts of the DORA Science Coalition to address research assessment and encourages the informed and rational use of citation data as a primary source of performance evaluation. No one metric can fully capture the complex contributions scholars make to their disciplines and many forms of scholarly achievement should be considered.

Bearing this in mind and in working with members of the scholarly community, Thomson Reuters offers various metrics that go beyond the Journal Impact Factor. With the recent integration of the Journal Citation Reports (JCR) and Essential Science Indicators (ESI) into the Thomson Reuters research analytics platform, InCites, it is now possible to view citation statistics at a granular level, whether by document type (i.e. article, review and proceedings), journal name, individual, organization or research area. This includes document counts, raw citation counts, average citation counts and normalized indicators.

Thomson Reuters is evaluating the inclusion of median values of citations, but not just at the journal level. In order to accommodate the skewing of citations, it is critical to also assess other entities within the research ecosystem. Thomson Reuters current approach relies on the input and feedback from existing customers and users, up-to-date research and practice in the field with rigorous testing by experts and stakeholders.

The Journal Impact Factor (JIF) is singled out in the San Francisco Declaration not for how it is calculated, but for how it is used. Still, with recent enhancements to InCites, Thomson Reuters has taken significant steps toward increasing transparency around the calculation of JIFs. The JCR now offers users greater visibility by directly linking an Impact Factor calculation to its list of citable items within the Web of Science, providing a view into each journal item included in the calculation.

Thomson Reuters would like to provide information on what the JIF is uniquely able to offer, in support of its correct use.

A JIF considers the citation performance of a journal as a whole unit, more than the sum of diverse published items. It is based on the cited references generated by the scholarly community, compiled objectively across thousands of journals and proceedings on an annual basis. Each title's JIF contains a single, current year of citations to the prior two year period, scaled according to a count of the quantity of scholarly material published in that same title over the same timeframe. Journals cannot dominate the ranking simply by their volume of published items. What generates journal impact is having a large number of citations compared to the volume of scholarly content.

The JIF does not measure the quality of an individual article in the journal — since it is not based on the citation of individual publications — but it does correlate to the reputation of the journal in its field. The editorial process strives to ensure the quality of the scholarship and the relevance to the audience of every article published. Each item selected for publication in the journal is subjected to this same editorial oversight and peer-review that is applied to all materials published in the journal. Scientists and scholars contribute their time and effort as reviewers and editors, to ensure the quality of the journals that matter to them. Over time, this editorial attention gives the journal a reputation for relevance and excellence. It also has the potential to result in a higher JIF compared to other publications with similar subject matter. The choice of a journal in which to publish is not unimportant, but appropriate publication venues should be topically relevant and scientifically appropriate according to the content of the article. These characteristics of a journal are not included in the JIF calculation.

The Thomson Reuters scholarly research and discovery platform, Web of Science, is home to various citation indexes and was developed from the same production data used to create the JCR, but presented at the level of individual published items. Items and their citations in Web of Science can be considered on their own or grouped by author, institution, department, field, etc. InCites utilizes the content and citation metrics within the Web of Science as the foundation for objective analytics that evaluate research output, performance and trends; understand the scope of an organization’s scholarly contributions, by individual or team; and articulate actionable outcomes to refine research priorities.

Thomson Reuters continues to encourage publishers, researchers and funders to consider the correct use of the many metrics available, including the JIF and other data from InCites, such as Essential Science Indicators (ESI)—a tool for determining the leading researchers, institutions, regions, publications and papers within a specific field of science—when performing research assessments.


Methods for the preparation of the Journal Impact Factor

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