Many thanks to Justin Dise and the Librarians of Daemen University for allowing us to reuse and adapt their guide Research Impact and Scholarly Metrics.
Scholarly metrics, or bibliometrics, is the quantitative method of measuring the impact of published research. The metric most people may be familiar with is Journal Impact Factor, but there are metrics available for use at the journal, article, and even author level. Each metric can be useful, but when used alone or out of context it only tells a part of the story.
This guide will explain the metrics available, how they're calculated, and how best to use them.
While metrics can offer great insight, it's important to understand when to use each metric and how to appropriately place them in context.
For example, don't use journal metrics to evaluate a researcher, as this doesn't offer any insight into how many times that author's work has actually been cited. You would want to use article-level metrics in conjunction with author-level metrics.
Work in some disciplines naturally have higher citation rates than works in other disciplines. Medical or life science articles, for instance, generally get cited more than articles or books in the humanities. Thus, comparing a journal's impact factor or an author's citations across different disciplines can be problematic. When comparing journals or an author's scholarly output, always do so in the context of that specific discipline and/or use metrics that are field normalized.
In addition to accounting for disciplinary differences, you should also consider the stage of a researcher's career when evaluating author-level metrics like bibliometrics and h-index metrics. A scholar just beginning their career likely won't have accumulated the same number of citations as a tenured scholar with 20 years of scholarly output.