Impact metrics and science evaluation

Scientists have always looked for ways to evaluate research results to recognize and reward their efforts, and to support decisions regarding programs and public policies. The metrics of scientific impact have become, in recent decades, the driving force behind the academic environment. The work of researchers, scientific journals, databases and publishers, research institutions, and funding agencies is driven by the impact of the research they produce, publish, index, promote and finance. Bibliometric indicators are widely used for the evaluation of scientific output, despite the lack of a clear relationship between citations and quality, impact, or scientific merit. Furthermore, the relationship is even less evident regarding innovation, which is an inherent characteristic of scientific research. This article describes the main types of metrics used to evaluate scientific output, as well as its features, potentials, and limitations.