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v2026.1714 entries · CC-BY 4.0
Dictionary termTrack EStablev2026.2

h-index

A researcher-level metric proposed by Jorge Hirsch in 2005, defined as the largest number h such that the researcher has published h papers each cited at least h times.

ByCASRAI Editorial Board
· Last updated 21 May 2026

Examples

Worked examples

  • Is an instance

    A bibliometric study reports h-index distributions across a field as context for further analysis.

  • Is an instance

    A scholar discloses their h-index with a caveat about field norms in a reflective piece.

Counter-examples

Looks similar, but isn't

  • Not an instance

    Comparing h-index across disciplines as a ranking criterion in hiring.

  • Not an instance

    Setting an h-index threshold for promotion eligibility.

Editorial commentary

The h-index is computed from a citation list by sorting papers by citation count in descending order and finding the largest h where the h-th paper has at least h citations. It conflates productivity and impact in a single integer. The metric is field-dependent (citation cultures and densities differ widely), time-dependent (it can only grow), database-dependent (Google Scholar, Scopus and Web of Science return different values), and insensitive to highly cited outliers above the threshold. Responsible-assessment frameworks (DORA, Leiden Manifesto, CoARA, Hong Kong Principles) explicitly caution against using h-index for hiring, promotion or funding decisions.

References

  • Hirsch JE, PNAS 102(46):16569-16572, 2005. Bornmann L & Daniel HD 'The state of h index research', 2009.

Also known as

Hirsch index · h

Machine-readable encodings

Use in your systems

JATS XML <role> element
xml
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Schema.org DefinedTerm (JSON-LD)
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