Major Indexing Service Calls Out Cardiology Journals for Self-Citation

Ivan Oransky, MD

June 30, 2020

More than 70% of the citations in one journal were to other papers in that journal. Another published a single paper that cited nearly 200 other articles in the journal.

Now, Clarivate, the company behind the Impact Factor, is taking steps to fight such behavior, suppressing 33 journals from their indexing service and subjecting 15 more to expressions of concern — all for apparent self-citation that boosted the journals' rankings.

The list includes some of publishing's biggest players: Nine journals published by Elsevier, seven by Springer Nature, six by Taylor & Francis, and five by Wiley.

Five of the suppressed or flagged journals are in cardiology, including JACC: Cardiovascular Imaging , which has an Impact Factor above 10, ranking it in the top 10 journals in the field. Three other cardiology journals given an expression of concern by Clarivate have Impact Factors above 5.

Three of the other journals subjected to an expression of concern were in allergy and immunology, and several others in the field of neurology.

Given many universities' reliance on journal rankings to judge researchers' work as part of tenure and promotion decisions, Clarivate's suppression of a journal — meaning denying it an Impact Factor — can have far-reaching effects. Impact Factors are based on average citations to articles in a journal over a particular period of time. Many, including Retraction Watch, have argued that Impact Factor is not the best way to judge research — for reasons including relative ease of gaming such metrics.

Clarivate's Web of Science indexes 21,000 journals, but only 12,000 are included in the annual Journal Citation Report (JCR) and receive Impact Factors. There are currently two reasons for suppression from the JCR: journal self-citation and "citation-stacking," behavior which is sometimes referred to as taking part in "citation cartels" or "citation rings." None of the suppressions or expressions of concern this year were for citation stacking. When the company suppresses a journal from the JCR, it continues to count its citations, but does not assign it an Impact Factor.

The company has changed the way it considers self-citation and revised its methodology, Web of Science editor in chief Nandita Quaderi said, in response to patterns it's observed in the past few years.

This year, Clarivate also subjected 15 journals to editorial expressions of concern. Such journals had small numbers of articles with very high levels of citation to articles in the same journal that can have a significant effect on Impact Factor and rankings. Looking only at overall journal levels of self-citation would miss such patterns, Quaderi said, because it would not take directly into account how these citations are "concentrated" in particular articles or time periods.

Nothing changes for JCR journals subject to such flags, but they are monitored closely for re-evaluation and may lose their Impact Factors in succeeding years, or be removed from indexing altogether.

This move marks only the second time that Clarivate has issued expressions of concern. In 2018, they did so for five journals in the bone field, four of which went on to be suppressed the following year. All five are now reinstated in the JCR, Quaderi told Retraction Watch.

At least 25% of the references in all of the suppressed journals were self-citations, with 71% of the citations in one journal, the Journal of Environmental and Engineering Geophysics, to other papers in that journal. Leading the pack of those journals subjected to an expression of concern was the Journal of Cleaner Production — with more than 11,000 self-citations, out of some 47,000 references, for just under 25%. One article in the Journal of Allergy and Clinical Immunology-In Practice cited other papers in the same journal 191 times.

Publishers of the journals affected by yesterday's announcement said they were reviewing the new listings.

"We support Clarivate in their efforts to maintain the integrity of the scientific record," an Elsevier spokesperson said. "Unusual self-citation patterns can arise for various reasons, including a journal covering a very niche discipline or publishing articles with unusually high concentrations of self-citations. We are working closely with the Editors (and our society partners in the case of society owned journals) to analyse the specific self-citation pattern of each journal and, if necessary, to improve practices for the checking of references for quality and integrity."

Alison Mitchell, Springer Nature's Chief Journals Officer, told Retraction Watch: "Obviously we take all concerns raised about our journals seriously and impact factors are an important (but not the only) metric by which our journals are judged. At this point we're still looking into the concerns raised, so we can't comment further."

"We have received the JCR confidentially and are under strict embargo until it is released by Clarivate, so we have not yet been able to share or review the report with our partners," said a spokesperson for Wiley. "We can follow up with more insight next week, after further analyzing the results and having a chance to communicate with our partners."

This report first appeared on Retraction Watch.


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