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Measuring Your Research Impact

Tips and tools for assessing the impact of journals, journal articles, and researchers

Journal impact factors

Journal impact factors are calculated and reported annually by Clarivate Analytics' Journal Citation Reports (WSU subscription). As of 2019, Journal Citation Reports includes over 11,800 leading scientific journals.

Journals with higher impact factors publish articles that are cited a greater number of times, on average, than journals with lower impact factors. For example, if a journal has an impact factor of 4 in 2017, this means that articles published in 2015 and 2016 were cited 4 times, on average, in 2017.

Caveats to using journal impact factors

Impact factors should not be compared across different disciplinesDifferent disciplines vary in their publishing and citation practices, which can influence the magnitude of journal impact factors. Journals in the life sciences tend to have the highest impact factors, and basic science journals tend to have higher impact factors than clinical medicine journals.

Impact factors should not be used to evaluate individual articles. In any given year, a small proportion of articles (20%) published in a journal account for most (80%) of that journal's citations; therefore, publication in a high impact journal does not mean that the article is frequently cited. Also, the scientific quality of a study does not always correlate with journal ranking. 

Impact factors should not be used to evaluate researchers. It is common for hiring panels, T&P committees, and granting agencies to evaluate researchers based on the impact factors of the journals in which they publish. This practice of rewarding researchers based on publishing in high impact journals can skew scientific progress by encouraging scientists to restrict their research to topics that are more likely to be published in top journals.

Further reading

P.O. Seglen. (1997). Why the impact factor of journals should not be used for evaluating researchBMJ, 314(7079): 498-502.

E. Garfield. (2006). The history and meaning of the journal impact factor. JAMA, 295(1): 90-93.

S. Saha, S. Saint, D.A. Christakis. (2003). Impact factor: A valid measure of journal quality? JMLA, 91(1): 42-46.

R. Monastersky. (2005). The number that's devouring science. The Chronicle of Higher Education

A. Casadevall, F.C. Fang. (2014). Causes for the persistence of impact factor mania. mBio, 5(2): e00064-14.