Eingang der Zentralbibliothek mit Treppe am Campus Virchow-Klinikum

Impact factors compared

The most well known metric for a journal is perhaps the 2 year impact factor, found in Journal Citation Reports. However, there are other similar metrics available. This page outlines the difference between the metrics that are available in our databases.

You are here:

Databases with bibliometric information based on citation analysis (impact factors)

The databases shown in this table can be used to check journals for their relative importance within a discipline; to rank at departmental or country level; or for authors to select journals for their future publications.

You can find important information on problems with the application of the impact factors in these publications, among others:

Impact factors compared

Database

Journal Citation Reports - Impact Factors

SJR SCImago Journal & Country Rank

SNIP - Source Normalized Impact per Paper

Access

Charité-License:


https://jcr.incites.thomsonreuters.com/

Free access:


www.journalmetrics.com


http://scimagojr.com/

Free access:


www.journalmetrics.com


http://www.journalindicators.com/

Subject area

Science, engineering, medicine, and social sciences

Science, engineering, medicine, and social sciences

Science, engineering, medicine, and social sciences

Sources / evaluated journals

ca. 11.500 Journals, Conference proceedings

ca. 18.000 journals, Conference proceedings and book series

ca. 18.000 journals, Conference proceedings and book series

Based on data from

Web of Science

Scopus

Scopus

Description

Impact Factor indicates the average citation rate of a journal's articles in a given year. It can serve as an indicator of the "relative importance" of a journal within a discipline.

SJR is comparable to the JCR impact factor. However, the calculation of the SJR includes a weighting for the prestige of a citing journal.

SNIP is an indicator of the average citation effect for articles in a journal. It takes into account the citation potential in the subject field.

Calculation

Quotient from the


 


- Number of citations in the JCR year


- by total number of articles published in the 2 (or 5) previous years


- all citations are treated the same

SCImago uses its own mechanism for ranking scientific journals, which is based on Google's Pagerank. SJR builds on the concept that citations are not equivalent. Accordingly, citations in journals with a high SJR value are more weighty than citations from a source of lower SJR rank.

SNIP takes into account the differences in citation practices between different disciplines. It accounts for the timeframes in which works are cited. This makes it possible to compare journals of various disciplines

Evaluation period

2 years or 5 years

3 years

3 years

Reporting period

from 1999

from 1999

from 1999

Updated

Each year (Annually)

Twice a year (Biannually)

Twice a year (Biannually)

Ranking / Comparisons

By subject area, country and publishers

By subject area and country

By subject area

Creator

Clarivate Analytics (originally Thomson Reuters)

SCImago Reseach Group and Elsevier

Center for Science and Technology Studies (CWTS) at Leiden University (Netherlands) and Elsevier