By Ruth A. Pagell*
(10 Nov 2020) Ruth’s Rankings regularly revisits journal metrics, covering legitimate and illegitimate sources and metrics. This will be a two-part article. Part one focuses on Journal Citation Reports™ Journal Impact Factor™ and other Clarivate Analytics products with journal metrics. JIF™ is a trademark of Clarivate Analytics and cannot be legally used by anyone else.¹
How do journals get into JCR?
“…Journals are selected for the Web of Science Core Collection. Journals in the Science and Social Science editions are included in JCR, and those with sufficient data to calculate a JIF receive the JIF metric “ (Sechler, 2020). CA added 351 this year. JCR has a suppression policy, identifying questionable citation practices. Journals suppressed in one year remain in WOS and can return to JCR. Click here for a list of suppressed titles.
How many journals are in JCR?
Web of Science Core Collection includes SCIE (Science Citation Index Expanded), SSCI (Social Science Citation index), AHCI (Arts & Humanities Citation Index) and ESCI (Emerging Sources Citation Index). Only SCIE and SSCI are in JCR. Some journals are assigned multiple subject categories. Open Access is OA Gold from DOAJ.org. About 10% of all DOAJ titles are in JCR.
|COLLECTIONS||TOTAL||OPEN ACCESS||JCR||JCR and OA|
|WOS Core Collection||21,424||4,732||12,056||1,662|
|SSCI (Social Science)||3,519||258||3,469||247|
|AHCI (Arts & Humanities)||1,847||106||440||20|
|ESCI (Emerging sources -not up to standards of other three)||7,754||2,923||Not eligible||Not eligible|
From Master Journal List Oct 13, 2020 and JCR released in 2020. Numbers from Master Journal List and JCR differ because MJLL is updated at least monthly and JCR is updated annually.
How are journals ranked in JCR?
The default sort order is current JIF for all journals in the database. Figure 46.1 below lists all sortable indicators. Subscribers can select indicators to display and download for each year’s dataset, from 1997.
CA-A Cancer Journal for Clinicians has had the highest JIF since 2005. Its current JIF is on its website. Using data from selected years, Table 46.1, with rankings and analysis, reflects changes in scholarly publication patterns. In 1997, three of the top ten publications were annual reviews. In this JCR, the highest ranking annual review is 30. New England Journal of Medicine is the only journal in the top 10 in 1997 and 2020. Only four are in the top 20 for both years. The number is limited because nine of this year’s top 20 titles were not published in 1997.
Drill down to specific research areas for more meaningful results. A good JIF for one category is mediocre for another. For example:
- Academy of Management Annals is tops in two SSCI categories, Management and Business, and is 238 overall.
- Scientometrics, publishing the most articles on bibliometrics, is in JCR categories in SCIE as Computer Science, Interdisciplinary Applications, ranked 45 and 2,942 in SCIE; and in SSCI, Information Science, Library Science, ranked 21 and 556 in SSCI. Overall, it is 3,506. Do not be deceived by the rank. It is in the top 60% in the SCIE category, the top 76% in the Information Science category, and the top 73% overall.
See Guide to Finding Journal Information for hints on how to find legitimate JIFs.
Which WOS research area has the highest impact?
WOS has 236 research areas. Table 46.2 includes 48 categories, listing the top 20 categories for total citations, aggregate impact factor, median impact factor and number of journals in a category. The table is ranked by citations, illustrating that more citations may not result in higher scores.
Number one for each category is shown below. Nanoscience and Nanotechnology has the highest Aggregate Impact Factor, which has an equivalent calculation to the JIF for a journal:
|Total Citations||Materials Science, Multidisciplinary||SCIE|
|Aggregate Impact Factor||Nanoscience and Nanotechnology||SCIE|
|Median Impact Factor||Cell Biology||SCIE|
|Number of Journals||Economics||SSCI|
|Aggregate Immediacy Index||Computer Science, Cybernetics||SCIE|
JCR and OPEN ACCESS
In April, Nandita Quaderi, Web of Science’s Editor-in-Chief, introduced open access metrics in JCR. She stated that it shows “how much of the scholarly literature is published using the gold OA model, and how much of this content is being cited…” It uses content published under a Creative Commons license (gold OA). This allows for “differentiation from subscription or free to read content (which may not be free to re-use.)” (Quaderi, N. 2020). See Appendix A and CA’s Quick Reference Guide on using OA data in JCR. Find definitions for the different OA categories and OA data in other CA platforms. Tables 46.A.1 and 2 are in the Appendix. It evaluates OA journals on different metrics and highlights the balance between quality and quantity and only pure gold OA with OA in hybrid journals. Living Reviews in Relativity is the highest ranked Gold journal, Scientific Reports has the most citable OA articles, and Science is the top 20 journal with the most OA articles of all types.
How many JCR titles are published in Asia/Pac countries?
1,144 journals are published in Asia/Pac, although some have Western parents. That is nine percent of today’s total and it was five percent in 1997. Most JCR journals are published in the U.S., U.K., Germany and the Netherlands, homes to Springer Nature, Elsevier, and Wiley. See Table 46.3 for the number of journals from each Asia/Pac country and the ranking for the top journal. China’s Cell Biology, ranked 82 and published by Springer Nature, tops the region.
JOURNAL METRICS FROM OTHER SOURCES
Ruth’s Rankings articles, listed below, cover the basics on metric providers. Table 46.4 compares the top 10 journals across providers and has more analysis. The table includes the providers using Elsevier’s Scopus dataset both as part of CiteScore and directly from SCImago’s SJR (SCImago Journal Rankings) and CWTS Journal Indicators SNIP (Source normalized impact per publication), and harvested rankings from Dimensions and Google Scholar Top Publications.
This year Elsevier’s 2019 CiteScore, includes more content, additional publishing years, and a one decimal score display. The new methodology has been applied back to 2013. A Scopus subscription is required to see more than top 1,000.
Digital Science’s Dimensions uses a harvested dataset at the article level, based on curated lists from the EU, Australia, China, and Norway and it includes humanities. Find out more about Dimensions in A Guide to Dimensions Data Approach. It has more documents than WOS or Scopus. The metrics available to nonsubscribers are citation mean (average) and median.
My last choice is Google Scholar Top Publications, although its publications are the most familiar. It ranks on H-index, based on citations generated by a computer program. SJR also has an H-Index ranking.
How should JIF and other journal scores be used?
Clarivate recommends using JIF with other metrics. The highest JIF score is over 200 and the MEDIAN for over 12,000 journals is 1.947. That leads to little differentiation in scores for the bottom 50%. Remember that there are millions of researchers and a limited number of JCR journals. Other metrics are needed to distinguish among these journals. These can be other JCR metrics or metrics from the other providers covered in Table 46.4 and other Ruth’s Ranking articles. JCR and the other journal ranking publishers provide one list of ranked journals per year and provide rankings by subject category.
- Use the subject category rankings
- Investigate the other metrics available.
- Check the journals’ websites.
Other issues to be addressed in a follow-up article are changes to the WOS/InCites platforms, Covid 19 articles challenging the old publishing model, including preprints and more retractions.
1. I have not used JIFs in the article. I have linked to journals I have mentioned that have metrics on their websites. Access to all Clarivate Analytics products require subscriptions except Master Journal List, which requires registration to see information beyond the initial list.
Ruth’s Rankings 4 – The big 2: Thomson Reuters [now Clarivate Analytics] and Scopus
Ruth’s Rankings 16: The much maligned journal impact factor
Ruth’s Rankings 37 Part 1: How important are journal quality metrics in the era of predatory journals?
Ruth’s Rankings 45: Insights into top factor: Journal impact reimagined
Pagell, R. (Nov-Dec 2014) Insights into Incites: Journal Citation Reports and Essential Science Indicators. Online Searcher. 38, 6,16-19
Quaderi, N. (Apr 2020). Introducing open access data in Journal Citation Reports. Clarivate Analytics Blog
Sechler, D. (Aug 2020), personal email from Product Development Manager, Clarivate Analytics
Szomszor, R. and Quaderi, N. (October 2020). Research Integrity: Understanding our shared responsibility for a sustainable scholarly ecosystem. https://clarivate.com/webofsciencegroup/wp-content/uploads/sites/2/2020/10/ISI-Research-Integrity-Report.pdf
Thanks also Kristen Faeth, Solutions Consultant at Clarivate Analytics and Jeff from Dimensions support team for their help on details for the article.
A list of Ruth’s Rankings and News Updates is here.
*Ruth A. Pagell is emeritus faculty librarian at Emory University. After working at Emory, she was the founding librarian of the Li Ka Shing Library at Singapore Management University and then adjunct faculty [teaching] in the Library and Information Science Program at the University of Hawaii. She has written and spoken extensively on various aspects of librarianship, including contributing articles to ACCESS – https://orcid.org/0000-0003-3238-9674