Impact Metrics

Originally suggested in 2005, an h-index is used to "quantify an individual's scientific research output" (HIrsch). The higher the h-index, the more impactful the author. It is a measure of scholarly significance, both the author's quantity and quality of research output. It is calculated using an individual's total number of articles and the total number of times those articles have been cited. Put another way, "a scientist has index h if h of his or her Np papers have at least h citations and the other (Np-h) papers have ≤ h citations each."

• Scopus (licensed)
• Google Scholar (free)

• Databased will likely produce different h-indexes for the same author due to different coverage
• Only compare h-index within a discipline
• Variants of h-index exist (g-index,a-index, etc.); only compare h-indexes within the same h-index tool
• h-index disregards authors' placement in authors' list
• Can be manipulated through self-citation