NIH's new citation metric: A step forward in quantifying scientific impact?

"Quantifying the scientific impact of publications based on their citations received is one of the core problems of evaluative bibliometrics. The problem is especially challenging when the impact of publications from different scientific fields needs to be compared. This requires indicators that correct for differences between fields in citation behavior. Bibliometricians have put a lot of effort into the development of these field-normalized indicators. In a recent paper uploaded in bioRxiv, a new indicator is proposed, the Relative Citation Ratio (RCR). The paper is authored by a team of people affiliated to the US National Institutes of Health (NIH). They claim that the RCR metric satisfies a number of criteria that are not met by existing indicators. The RCR metric has been made available in an online tool and has already received considerable attention. Stefano Bertuzzi, Executive Director of the American Society for Cell Biology, strongly endorses the metric in a blog post and calls it ‘stunning’ and ‘very clever’. However, does the RCR metric really represent a significant step forward in quantifying scientific impact? Below I will explain why the metric doesn’t live up to expectations ..."