|Year : 2016 | Volume
| Issue : 9 | Page : 619
The impact factor story: Part I
Editor, Indian Journal of Ophthalmology, Chairman, Managing Director, Aditya Jyot Eye Hospital Pvt. Ltd., Wadala (West), Mumbai, Maharashtra, India
|Date of Web Publication||17-Nov-2016|
Editor, Indian Journal of Ophthalmology, Chairman, Managing Director, Aditya Jyot Eye Hospital Pvt. Ltd., Wadala (West), Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Natarajan S. The impact factor story: Part I. Indian J Ophthalmol 2016;64:619
This issue has a very interesting manuscript titled “Trends in impact factors of ophthalmology journals” written by Vainer et al. The authors reported that they investigated and found that in the past few years, as the number of scientific journals has proliferated, the impact factor (IF) of the existing journals has gone up. At the various research methodology workshops conducted by the Indian Journal of Ophthalmology, one of the frequently asked questions is “What is the Impact Factor?” While there is a clear definition of what the IF of a journal is, what it means for a journal and its relevance to the reader at large remains a question that doesn't quite have an obvious answer. In this series of editorials, I hope to bring some clarity and also address some of the controversies surrounding IFs.
The term “Impact Factor” was originally developed by Eugene Garfield as a tool that reflected a journal's importance because the more often papers from a particular journal are cited by other authors, the higher the IF. For the mathematically inclined, the IF for a journal for a year, say, 2015 is based on the number of citations that appeared in indexed publications during 2015 to articles published in that journal during the preceding 2 years (2013 and 2014), divided by the number of “citable” papers published during those 2 years. The IF, therefore, is a measure that can be applied to any journal and essentially, it would give a measure of the frequency with which the “average article” has been cited in a particular year or period. The key idea behind the IF is citations and the number of them.
Recently, there has been a lot of criticism of IF and the suggestion that its usage and utility is hyped. While part of that may be true (I shall discuss that in detail in my next editorial), it is not as though IF has no beneficial role at all. As Scully and Lodge have pointed out, the IF is useful in clarifying the significance of absolute (or total) citation frequencies. It also eliminates some of the bias of such counts which favor larger journals over small ones, of older journals over newer ones or of frequently issued journals over those less frequently issued. Furthermore, even publishers often use IF for marketing and promoting the journal or in identifying opportunities for new journal launches or taking decisions on whether to expand, merge, or discontinue existing titles. Even researchers on occasions use the IF to decide where to publish their research.
However, as I mentioned, all is not well about the IF. Garfield, who coined the term IF, had suggested that the IF is not an absolute measure of the quality of a journal, but of its influence. Hence, choosing the IF as an evaluation instrument equates to a decision to measure influence and not, or not primarily, quality. Even Garfield initially intended the IF to be of help to librarians in selecting journals to which to subscribe to. However, it acquired iconic status as a single measure of the quality of science published in a journal and by extension, the scientific standing of authors, affecting, among others, grant allocation, and career advancement. Not that I have any issue with it being so, but is it qualified enough, reliable enough, and immune to manipulation to reflect a journal or a researcher's true merit? This will be one of the many things I shall also elaborate on in my next editorial apart from some of the other controversies surrounding IF, its uses, and how journals are “gaming the impact factor.”
| References|| |
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The impact factor game. It is time to find a better way to assess the scientific literature. PLoS Med 2006;3:e291.
Baethge C. Impact factor – A useful tool, but not for all purposes. Dtsch Arztebl Int 2012;109:267-9.
Brink PA. Article visibility: Journal impact factor and availability of full text in PubMed Central and open access. Cardiovasc J Afr 2013;24:295-6.