Understanding the Limitations of the Journal Impact Factor

Editorial: Self-citation in Publishing

“…There are numerous sources of potential bias in the rankings, some inherent in the system and some not: selfcitation (articles from the same journal), citation density (the number of references listed), quality of citations, poor comparability between different specializations, mainly use of English language in publications, type of manuscripts, ease of access, and journals not listed in the SCI database are major disadvantages of the IF [1,5,14,16,19,20,25,26,31,35,40,43,47,49]. Based on the IF, a citation from an important journal such as Nature is worth no more than a citation from journals in the lowest tiers of publishing [3,45].…”

“…Based on the IF, a citation from an important journal such as Nature is worth no more than a citation from journals in the lowest tiers of publishing [3,45]. Considering that the SCI database lists only approximately 5000 journals of an estimated total of 126,000 [36,47,52], 121,000 journals not listed in the SCI often are referred to as having no IF [35].…”

“…However, it is easy for editors to manipulate the IF. Editors may artificially increase their journal's IF by (1) facilitating (or even demanding) self-citation [11,12,24,27,39,42,47,48,50,51], (2) increasing nonsource items with citations, (3) limiting the total number of articles and/or the number of original papers and increasing the number of review and/or technical articles that are more likely to be cited [11,27,35,42,47,51], (4) encouraging ''salami slicing'' [4,22,37], and (4) prerelease or timing of publication early during a year thus allowing more time for citation for a given year [19,28,49,51]. Excessive self-citation may cause a large shift in a journal's IF, particularly if the total rate of citations of that specific journal is low [11,32,51]; one journal's IF increased 18 ranks by one paper containing 303 self-citations [32].…”

On indexing in the Web of Science and predicting journal impact factor

“…Yet, 'quality' itself is a subjective notion. We note that the IF certainly does not reflect the quality of the peer review process to which a journal subjects submitted articles (Kurmis, 2003;Benítez-Bribiesca, 2002). Some editors seek to understand the IF calculation so that they can manipulate it to their journal's advantage (Jennings, 1998).…”

Should editors influence journal impact factors?

“…Applying it as proxy for the quality of individual authors is both misleading and unethical as it has been clearly explained in the literature, and should by now be widely understood, that the journal impact factor is largely unsuitable for that purpose. 17,[40][41][42][43] The impact factor is an arithmetic mean of the citation rates of all authors of a particular journal during a two-year period, with an extremely high standard deviation, and relies on a biased and incomplete database. 1,[35][36][37] A comment by Eugene Garfield is pertinent here: 44 'The source of much anxiety about 3 I see nothing unethical if authors and journals try to increase this factorgiven that it is largely meaningless in this context.…”