Bibliometric indicators – h-index, JIF and citations
Research is continuously evaluated by various bibliometric indicators. This page explains several common bibliometric indicators and how they may be used.
Bibliometric indicators may be used on researcher CVs, in strategic decisions, or as part of evaluations. This page gives information about several common bibliometric indicators, including what they are for, what they show, and potential issues.
Bibliometric indicators for researchers
For researchers, the h-index is used most. This is a measure which combines the number of publications with the number of times each publication has been cited. It is affected by field and time, so is not comparable for researchers in different fields or of different scientific ages. More can be read about the h-index on PhD on Track.
You can find an author’s h-index in abstract databases such as Web of Science, Google Scholar or Scopus. Note that the h-index may vary between these sources, as they each count citations using publications indexed in their own database.
Nowadays, publication lists which include citation-counts are available online and are visible for everyone. Web of Science, Scopus and Microsoft Academic have begun automatically creating profiles for authors who have publications in their databases. You can check and “claim” these profiles if you wish to control and verify your own records. Read more about creating and maintaining your online presence here.
Bibliometric indicators for journals
For journals the impact factor (JIF) from ISI- Journal Citation Report (based on data from Web of Science) is often used a measure. The impact factor is calculated by the average number of citations each article in a specific journal has received. An alternative is the SCImago Journal & Country Rank which is based on the data from SCOPUS. Google Scholar Metrics offers a similar metric called h-index for journals.
In Norway, there is also a national system for journals. Academic journals are divided into two categories, nivå 1 and nivå 2, and these categories are used in the national performance-based research funding systems. You can search for journals and find out more about the Norwegian Register for Scientific Journals, Series and Publishers here. This list is also a good way to check if a journal is legitimate and not predatory.
Note that journal level metrics have a number of issues when it comes to evaulation, and should only be used at the journal level - not in evaluations of individual researchers or articles. Read more about this in the DORA declaration.
Trying to pick a journal to publish in? Factors to consider when picking a journal.
Bibliometric indicators for articles
The number of citations is often used for articles. The number of citations can be found in services such as Web of Science, SCOPUS, Google scholar or Microsoft Academic. You can establish a citation alert with these services to keep track of how many times a record or article is cited. Note that these databases may give different numbers as they have a different coverage for respective subjects.
Citations are sometimes talked about as a measure of the “impact” or “quality” of an article. While citations may give an indication of scientific impact, their reflection of other dimensions (scientific quality, societal impact) is debated (Aksnes et al. 2019).
Altmetrics are an alternative type of metric which was designed to focus more on the outreach of an article. Altmetrics do not look at citations in other research articles, but at mentions in social media, news outlets or policy papers. You can download the altmetric bookmarklet for your web browser to view these statistics for publications.
You can read more about these measures and criticism towards them on PhD on Track. The Metrics Toolkit also provides descriptions of various metrics, their limitations, and appropriate or inappropriate uses.