Researchers

A publication's reliability, integrity and quality needs to be considered when identifying where to publish. Evaluate publications in terms of the following attributes:

• peer review
• citation analysis indicated by impact factor or other ranking
• international editorial board
• international author base
• coverage by an abstracting indexing service

A lot of the above information can be gained by consulting the journal directly as this informatino is usually included on their website.

Journal metrics use citation data to rank and compare scholarly journals. Citation analyses are based on the premise that number of citations is an indication of the importance of a journal.

The status of a journal is commonly determined by two factors:

1. popularity e.g. number of citations a journal receives
2. prestige e.g. sources of a journal’s citations.

What is a 'Journal Impact Factor'?

"Impact Factor: The measure of the frequency with which the average article in a journal has been cited in a particular year. The impact factor will help you evaluate a journal’s relative importance, especially when you compare it to others in the same field. It is calculated by dividing the number of current citations to articles published in the two previous years by the total number of articles published in the two previous years." JCR information and help.

Impact Factor is one indication of the journal's relative importance and prestige. It may be useful when selecting a journal in which to publish. i.e. a journal with a high impact factor.

Web of Science and Scopus also provide information related to a journal's publishing impact. e.g. Scopus via the Journal Analyzer provides a SJR which is a measure of the scientific prestige of scholarly sources. However, you need to consult Journal Citation Reports (JCR) for the Impact Factor.

The 'H-Index' - is a measure of an author's publishing impact.

"The h-index is based on a list of publications ranked in descending order by the Times Cited. The value of h is equal to the number of papers (N) in the list that have N or more citations." Web of Science help.

Web of Science and Scopus provide h-index data, however the calculation may differ between the databases, as based on different journals and years covered by each database.  

• Individual articles should never be judged solely on the Impact Factor or other metrics for the journal in which an article is published.

• All journals have a spread of citations, and even the best journals have some articles that are never cited.
• Citation counts alone do not indicate the quality of the citations or the publication e.g. a work may be highly cited because it is controversial; this can distort the impact factor of a journal.
• Analyses are limited to the journals listed in the database you are using e.g. JCR results are limited to the journals in the Thomson Reuters database, explaining why many journals do not have an Impact Factor.
• JCR calculations are based on a 2 or 5 year citation window compared with 3 years for Scopus calculations. A shorter citation window favours rapidly moving fields whereas a longer citation windows favours fields which build citations more slowly.
• Citations may be biased e.g. English language and review journals tend to be cited more frequently than works in other languages; authors may frequently cite their own work or the work of their colleagues.
• Review journals tend to have higher impact factors than original research journals in the same field because they tend to be cited more frequently.
• Only research articles, technical notes and reviews are “citable” items. Editorials, letters, news items and meeting abstracts are “non-citable items” and so do not contribute to Impact Factors and other metrics calculated from citation data.

Scopus Journal Analytics is part of the SciVerse Hub, an Elsevier product. Scopus Journal Analytics data is updated twice a year in April and September.

Scopus is the citation data provider for the ERA 2012 evaluation.

The Scopus journal metrics, SJR and SNIP, normalize fields. This enables journals from disciplines with different citation behaviours (number and frequency of citations) to be compared.

SJR excludes journal self-citations above 33% of the total received by a journal. This ensures that an ‘artificial’ increase of journal self-citation stops having any effect when it surpasses standard journal self-citation practices.