Bradford’s law, the long tail principle, and transparency in Journal Impact Factor calculations

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Fernando Fernandez-Llimos


Journal Impact Factor, Reproducibility of Results, Selection Bias, Conflict of Interest, Periodicals as Topic, Bibliometrics


Beyond the commonly mentioned limitations of the Journal Impact Factor, we discuss the obsolete principle of selecting journals to create a fake-representative sample of ‘journals that matter’ and the opacity around the calculation and listing of Impact Factors. We use the example of Pharmacy Practice in 2015 for illustration. We hypothesize that a business-oriented system of measuring the science and quality of scholarly journals may not be the best option to avoid biases and conflicts of interest.

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