The Journal of Clinical Pharmacology, Clinical Pharmacology in Drug Development, and the Impact Factor.

Abstract

The Impact Factor (IF), a metric used to gauge the “importance” of a scientific journal, has existed for decades. In the past, academic organizations have reportedly used the IF to assist in decision-making about promotion and tenure, and other organizations have used it to assess funding applications. While editorials and commentaries have been written about the misuse of the IF,1, 2 it continues to live (and haunt) journal editors due to its inaccuracy and misuse. A brief understanding of how the IF is calculated will illustrate its inaccuracy in assessing a journal's “impact,” and how the IF can be easily manipulated. The IF calculation is the sum of the articles cited in a target journal over a 2-year time period divided by the total number of articles published in that journal over the latter, 1-year time period. While the numerator contains all journal citations (any content from a journal) published over the 2-year time period, the denominator contains only the articles designated as primary research articles or review articles.1 This is the classic “comparing apples to oranges” scenario. In addition, a single well-cited article can increase a journal's IF substantially.2 The ways to manipulate the IF include reducing the denominator (fewer primary research and review articles published in the journal), publishing more review articles (which are cited more often than most original research), and negotiation with the company that calculates the IF for revised article designation (to reduce the denominator).1 Other problems have been previously identified.3 Thus, the IF is a very flawed metric. How can the emphasis on the IF be reduced (or eliminated)? Casadevall and Fang4 proposed a number of suggestions, including support of the San Francisco Declaration on Research Assessment (DORA), the boycotting of high IF journals, development of diverse metrics, and reform of review criteria for promotion, tenure, and research funding. Recently the American Society of Microbiology, an organization with over 30,000 members, removed the IF from over a dozen of their journals.5 As journal editors, we support this action. The Editors-in-Chief of the two American College of Clinical Pharmacology (ACCP) journals, The Journal of Clinical Pharmacology (JCP) and Clinical Pharmacology in Drug Development (CPDD), proposed to remove the IF from the respective journal websites. The proposal was accepted by the ACCP Publications Committee and Board of Regents. We believe that in the 21st century, other metrics, such as full article downloads, illustrate directly the impact of articles published in these 2 journals. For example, full-text downloads for JCP have increased 300% in the time period 2013–2016. For CPDD, which was first indexed in 2016, full-text downloads tripled from 2015 to 2016. We urge readers of these journals as well as our fellow editors to reexamine the use and importance (or lack thereof) of the IF. We believe that this step sends the message that the IF is antiquated and misused, and other metrics should be explored to assess the importance and scientific impact of publications.