Journal and author bibliometrics

Bibliometrics is the quantitative analysis of research literature, based upon citations, and can be used to evaluate the impact on the academic community of a research paper, an individual researcher, a research group or institution, or a journal.

The most commonly used bibliometric indicators include journal metrics and researcher metrics.  Alternative (Altmetrics) metrics are now increasingly being used.

Why are bibliometrics important?

  • Bibliometrics can be used as an indication of the importance and impact of your work or that of a research group, department or university, and therefore of its value to the wider research community.
  • Applications for funding, research positions or promotion may require bibliometric data and you may choose to include it in your CV.
  • Bibliometrics are increasingly being used to measure and rank research output both within institutions and on a national or international level. University rankings may take bibliometrics into account and they are utilised in the Research Excellence Framework (REF).
  • Bibliometrics can be used as a tool to identify research strengths and inform decisions about future research interests.

Journal metrics

  • The Impact Factor is probably the most widely recognised journal metric. The citation data is taken from the Web of Science database and published by Clarivate as the Journal Citation Reports (JCR). There are separate editions for Science and for Social Sciences. JCR enables you to find information on leading journal titles in a subject field and compare the impact of individual titles, including Eigenfactor metrics.  

Researcher bibliometrics

  • The h-index (also known as the Hirsch index) was proposed in 2005 by Jorge E. Hirsch as a way to characterise the scientific output of a researcher. It uses a calculation based on the citation rates of an author's published papers to attempt to measure both the productivity and impact of a researcher.  Some of the limitations of the h-index include:

 - A highly-cited paper is counted regardless of why it’s being referenced e.g. for negative reasons.

 - Variations in average number of publications and citations in various fields (some traditionally publish and cite less than others) are not accounted for.

 - The number and position of authors on a paper are ignored.

 - It limits authors by the total number of publications, so shorter careers are at a disadvantage.

There will also be variations in the h-index according to the bibliographic source or the search engine used to calculate it as the sources will only gather information from the journals they index. For example Web of Science indexes over 20,000 journals and conference proceedings and Scopus indexes over 30,000 journals and conference papers, and citation data is primarily from 1996 onwards.

You can calculate your h-index on Scopus, Web of Science and Google Scholar Citations which is a free service provided by Google which collates your work into one profile. The profile can be kept private or made public. The benefits of using Google Scholar Citations include a simple graphic to identify what your h-index is.

  • Citation analysis - find out how many times your publications have been cited on journal and citation indexes such as on Scopus and Web of Science.

Citation counts alone should not be used as the only measure of research quality. Different sources can produce different figures, and data should be used with caution, especially if comparing across disciplines.