The importance of scientific findings is generally considered in terms of the impact that those findings have in the scientific community. As impact itself is a somewhat vague concept, scientists rely on citations as a metric for measuring impact. The Impact Factor of a journal is based on the number of citations that published article receive, and authors themselves can track the total number of citations their publications have received.
Despite the importance that citation data play in the scientific community, there had previously been no investigation into the prevalence of self-citation. However, in August of 2019, researchers published a study in PLOS Biology in which they performed a thorough analysis of the citation metrics that are used by publishers and individual researchers.
In their analysis of the 100,000 most-cited authors across a range of scientific fields, the authors were able to determine that the median percentage of self-citations is 12.7%. However, the authors also identified cases of “extreme self-citation” in which small groups of authors were responsible for a very large percentage of citations among each other’s publications.
While there is no rule against self-citation and in highly advanced specialties it is often essential, it is important for scientists to be aware of this issue and the potential for abuse. The results of this study will help the scientific community to improve the use of citation metrics and hopefully prevent their abuse.
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