Scientific Journals (IF): Science Impact Factor

Scientific Journals (IF): Science Impact Factor

Scientific Journals (IF): Science Impact Factor

Official science and researchers publish a large number of materials annually. There are also many publications in which such articles are posted. Choosing a journal for his content, the author takes into account various criteria: topics, terms of publication, the need to pay for publication services, etc.

But how to identify the significance of a journal for science? How many readers will familiarize themselves with the material published in a particular journal, and perhaps cite it?

In order to rank publications in importance for representatives of science, various indicators are used, which are called impact factors (IF), and they are also called influence factors. The impact factor of the journal is one of the main criteria by which the usefulness of the journal and the materials posted in it are revealed. IF often helps to decide on financial support for scientific research, hiring workers for a scientific position, etc. IF also takes into account when selecting materials for subscription in libraries of an experimental direction.


v Science Impact Factor

The determining criterion for the importance of scientific journals in the world of modern science is the impact factor of the journal. The number of publications is increasing daily, both in domestic and foreign literature. What periodicals to subscribe to, where published studies are most valuable, how to boost credibility, or find useful information for your own article? Impact factor is a scientometric tool that allows you to determine the aggregate indicators of not only the significance of the published journal but also the relevance and productivity of the scientific activity of a scientist or organization.

Impact Factor is the most significant parameter of a scientific journal; it is expressed as a number and reflects the significance of a particular publication. Introducing of IF in the 50s of the last century was proposed by employees of WoS, USA. To this day, this index is used by scientific institutions to determine the degree of importance of a publication.

v What is the impact factor of a journal?

The impact factor of the journal (impact factor, IF, JIF) is a numerical indicator of the significance and popularity of a periodical. This mechanism was first used in the 60s of the 20th century in the United States. Specialists of the Institute of Information proposed to evaluate the quality of periodicals by quantitative characteristics, namely, by the number of citations or references to articles in this journal.

v Methodology for calculating the impact factor

The method is based on calculations based on links to the journal published in its publication. There are various approaches to estimating the impact factor of a periodical: in two, three, five previous years. Some scientific organizations use classical methods of counting, while others use specific, independently developed methods.

How exactly is the impact factor of the journal calculated? 

The classic technique of popularity of a periodical:

IF 2017 = a / b,

Where (a) - the number of articles cited in 2017 published for the previous conditional period (2 or 5 years) - 2015-2016 or 2012-2016,

(b) - the total number of all publications for the same conditional period.

That is IF is calculated for the year of citation, following a certain period of publication. Articles published over the past two years are not included in the IF count.

v Essential features of Impact Factor

Even though the impact factor is widely used as a scientometric indicator for evaluating journals, it has three critical features:

  • The formal number of citations is not always related to the quality of scientific papers.
  • It is not correct to compare the performance of journals from different fields of science, since they traditionally may have different frequency of publication of the results. For journals in rapidly developing practical sciences (for example, medicine, biology), in which the rate of publication of works is higher, the impact factor is many times greater than that of journals in the exact sciences (mathematics, physics).
  • For estimation, it is better to use the impact factor for a 5-year period, since citations do not begin immediately after publication, but, as a rule, with a delay of several years, and in journals with a long publication process, authors may already refer to works falling into the 2-year interval. 

v Advantages and disadvantages of Impact Factor

The impact factor allows, for formal reasons, to compare different journals and research groups. The impact factor as a scientometric criterion has the following advantages:

  • Ease of understanding and use.
  • Comprehensive coverage of scientific literature (in 2010, WoS indexed over 16,500 journals from more than 60 countries).
  • The results of its calculation are public and easily accessible.

At the same time, the impact factor has some limitations and disadvantages of both a technical and methodological nature. The latter usually include the following:

  • The number of citations (as well as the number of publications) is, in fact, far from always related to the quality of the study.
  • Most researchers believe that the two-year interval in which citations are taken into account is too small. Classical articles are often cited even several decades after publication. Also, in journals with a long publication time, reports regularly refer to works that do not fall within the three-year interval (to a lesser extent, this drawback is inherent in the five-year IF).
  • For different areas of research, a different frequency of publication of the results is also characteristic, which has a significant impact on the impact factors of journals (for example, in 2003 the average impact factors for the disciplines were: cell biology - 5.6, organic chemistry - 2.2, mathematics - 0.5)

v Conclusion

We learned that the impact factor of the journal is one of the most significant scientometric characteristics of the journal. It should be understood that the IF reflects a formal assessment and does not take into account the quality of scientific work. And when comparing journals, it’s better to look at indicators for a longer (5-year) period.

·         The WOS Impact Factor is a JCR indicator that is defined for foreign journals and is posted in the Journal Citation Reports; it is located at, but only users of organizations with the appropriate subscription have access to it.

Do not forget that SJR and JCR are calculated exclusively for journals that were in the information databases at least two years ago (Scopus) and at least four years ago (WoS) since younger publications are not yet indexed.

·         To compare the degree of importance of journals from various scientific fields, it is better not to use IF, but Quartile, which is also determined by WOS databases and posted on their websites.