"Research impact" refers to the influence of a scholar's work. Tools to track and measure impact are designed to help researchers understand how their work is being used and how it fits into the scholarship of their field overall. A scholar might ask, for example:
Understanding the impact of one's research can help scholars build tenure and promotion cases, select publication outlets for future work, and identify potential collaborators.
The research metrics and tools described on this guide help researchers to quantify some measures of the influence of their work.
Metrics that quantify the use of scholarly publications are available at three levels.
Article-level metrics include any measures of the influence of a single publication. The most metrics are available for journal articles, but some can apply to books, chapters, or other individual publications. They include times cited, article downloads, and most Altmetrics.
Author-level metrics aggregate the metrics of all of an author's publications to summarize his or her career overall. These metrics include the h-index and related measures, as well as citation totals.
Journal-level metrics are intended to describe the influence of a journal overall. The Journal Impact Factor is the most widely used metric at this level.
Most metrics at all three levels are based in counting citations among scholarly publications. Some emerging metrics (Altmetrics) assess other measures of use and influence, such as the number of times a publication is read, downloaded, saved, or cited in popular sources.