Thomson Reuters unfairly targets small journals and niche titles. This policy can result in the quicker death of some research topics that could otherwise thrive.
Thomson Reuters can suppress a journal from the Journal Citation Report for one review article it has published. How is this possible?
A review article can frequently include hundreds of citations. If some of them link to a specialized, niche title that covers the topic of the review article, they may represent a substantial share of all the citations received by this small journal. And this might be treated as “citation stacking” and result in the loss of Impact Factor for both titles.
This is nothing unusual. Many established researchers are expected to write reviews of current works in their fields, and all of them tend to cite several journals, which are in their opinion the best sources of literature. This phenomenon, especially in the case of a niche topic, may result in a large proportion of all citations to a specialized venue coming from one review.
This is a normal occurrence. But if the citation share from one source exceeds an arbitrarily chosen value, Thomson Reuters may identify it as an example of “citation stacking”, so an “extreme outlier in citation behaviour”, that causes “significant distortion of the (recipient’s) Journal Impact Factor and rank that does not accurately reflect the journal’s citation performance in the literature.” We already know the case of one review article that resulted in such a diagnosis.
Interestingly, publishing a review that includes the same number of citations to a “recipient” journal may result in the suppression of both journals in one year, and with no effect in several other years. This is possible, again, if the “recipient” journal is small. Citations to smaller journals tend to fluctuate significantly, and a “donor” journal may be unlucky enough to publish a review in the year when the “recipient” received a smaller number of citations than it usually does from other sources. As a result, the proportion of citations brought by a single review will increase, and Thomson Reuters will detect an “extreme outlier in citation behaviour”.
Therfore, Impact Factor loss can be the result of an unfortunate coincidence that can occur in the case of virtually any review article in a field covered by a niche journal. And this coincidence will automatically result in the loss of Impact Factor by both “donor” and “recipient” journals. Both journals will be banned from the Thomson Reuters’ database and due to suppression will completely lose Impact Factor.
As a result, the Thomson Reuters policy unfairly targets small journals and niche titles. Moreover, it can also lead to the quicker death of some research fields that could otherwise thrive, by destroying the most important journals operating in these fields.
This would not be as bad in the case of any other metric or indexing service, but the Impact Factor is a very special metric. Some call it the most misused metric in the academic world. It has a huge impact on science, which some commentators consider to be devastating.
The Impact Factor is the quotient of the number of citations received in a year by the papers published in a journal in the two preceding years and the number of papers published in those two years. It was designed to rank journals (e.g. to make a decision which journal to subscribe to easier for librarian) but nowadays it is also widely used as a proxy of the quality of a paper and its author. Researchers are judged by funders, supervisors and promotion panels by the Impact Factor of the journal they publish in. In some countries the funding available to researchers depends on the Impact Factor of journals they previously published in. It puts researchers under huge pressure. And this pressure affects publishers as well, as they now care more for Impact Factor than any other editorial and publishing issue. And at the heart of this system is one company, which has to cope with a huge responsibility for the whole edifice of science. So, in the end, it is not surprising that this company makes mistakes.
Image: Fresh impact crater on Mars showing a prominent ray system of ejecta. This 30 m (98 ft) diameter crater formed between July 2010 and May 2012 (19 November 2013; 3.7°N 53.4°E). Public Domain. Source: Wikipedia.