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Research Impact and Citation Analysis

Limitations

Journal Impact Factor is only one metric by which journals can be compared. What are some other ways to determine a journal's impact, quality, or relevance?

How many patents cite a journal? You can find this out at Lens.org, a free agglomeration database which harvests bibliographic data from PubMed, Crossref, and other sources. Or how about public policy documents, government reports, and statutes?

Search in Lens.org for the journal JAMA Surgery with a mouse highlight over the 71 patents which cite items from the results set

 

Interested in reviewing journal quality? One way is to browse the journal's contents. Review the subject matter, and note its relevance to your work. Pick a sampling of articles and study their research methods sections -- do the methods seem rigorous? You can also check the journal's editorial policies around rigor. Does the journal employ statistical reviewers, if relevant? 

Cabell's Journalytics and Predatory Reports give a number of potential factors to review while evaluating journals. Does a journal falsely claim to be indexed in an academic database? Is there a clearly stated peer review policy on the journal website? Does one managing editor appear to be the editor for dozens of journals? Is the editorial board listed?

All these and more are questions a researcher should ask when comparing journal impact, quality, and relevance.

Comparing Journal Impact Factor

In this tutorial, we’ll be using Journal Citation Reports (JCR) from Clarivate. JCR has two metrics of interest, journal impact factor (JIF) and the journal citation indicator (JCI). 

Journal Impact Factor (JIF) is a Clarivate metric. In any given year, the impact factor of a journal is the average number of citations received per paper published in that journal during the two preceding years. The impact factor is based on two figures:  the number of citations to a given journal over the previous two years (A) and the number of research articles and review articles published by that journal over the same two-year period (B), so:  A/B = Impact Factor (JCR). There is also a separate 5-year JIF, which applies the same formula for citations to a given journal over the previous five years, rather than two years.

Journal Citation Indicator (JCI) is a three-year average of a field-weighted metric called CNCI, itself a ratio between number of citations to a journal and the number of expected citations to a journal. How the expectations are calculated is a black box which Clarivate does not reveal. The end result of the JCI is a number which is supposed to be comparable across disciplines. If a journal is given a JCI of 1.0, it is exactly the global average for citation impact. If a journal is given 2.0, it’s impact score is twice the average. In other words, Clarivate frames having a higher than 1.0 JCI as desirable. 

There are many other ways to evaluate journal quality other than simply using these metrics – please see the Considerations and Context section for more. For now, we’ll look at how to retrieve and compare JIF.

First, connect to Journal Citation Reports. Sign in with your Clarivate credentials (the same ones used to sign into Web of Science) to create saved Favorites lists.

 

Starting with specific journals

Go to Journals at the top and search for a journal name, Click Enter when your desired result appears, or click “see 1 result”. For our purposes, this is better than than clicking the name of the actual journal when it appears; clicking it would open a new window with information about the journal itself.

Journal Citation Reports search result with Lancet Microbe checked off

Check off the correct box. Your boxes will stay selected until you consciously choose to deselect them at the bottom. So, if you like, you could just get through your list of up to 50 journals for comparison and add them all to a Favorite list at once.

Once you have selected all the journals you’d like to compare, click the Add to Favorites list button. Make a new list if applicable.

Black bar showing 5 journals selected and the button option to Add to Favorites

Pop-up box prompting user to Choose or create a new list to add your favorites.

If your journal doesn’t come up by name, try using ISSN instead. Search for the journal online or in Franklin Catalog to find their ISSN. Both print and e-issns should be listed for a journal, so it shouldn’t matter. 

To view the compared list, go to My Favorites, and click on your list.

My Favorites section in Journal Citation Reports, showing three favorite lists, including the Microbiology list

You should be able to compare attributes between all of the journals on that list, including journal impact factor.

Table of the five journals in the Microbiology list with each journal as a row and various metrics, including JIF, as column headers

For additional analysis, you can compare four journals at once using the Compare feature at the bottom of the screen, after the selection phase. This provides both JIF and JCI, but also additional visualizations based on OA, quartiles, etc.

Black bar showing four journals selected and the button option to Compare, which is next to the Add to Favorite List button, now activated

Four journals as column headers with JIF trend charts and JIF quartile, percentage, and rank by category below each column

 

Starting with a journal category

If you don’t know what journals you’d like to compare, but just want to compare a number of journals in a given category, go to Categories at the top, drill down to a category of interest, and click on the number of journals to view their comparison. You can also search for categories in the main search box.

Biology and Microbiology as a main category, with a list of 34 subcategories, including Microbiology

You’ll have the option to explore journals within a category in either the ESCI, the Emerging Sources Citation Index, or a more longstanding index, like the SSCI (Social Sciences Citation Index), SCIE (Science Citation Index-Expanded), and the AHCI (Arts and Humanities Citation Index).

Microbiology sub-category, broken up into two journal clusters: one in the ESCI and one in the SCIE

Here you can sort based on JCR, JCI, total citations, or %OA gold. You can also change the JCR year using the filters on the left. If you click on Customize toward the top of the table, you can see other metrics, such as article influence score, normalized Eigenfactor, 5-year JIF, JIF without self-cites, and more. You can also customize which metrics you’d like to see on the screen at once.

You can also click on any one journal name to look at all of these metrics with visualizations for that one journal.

138 microbiology journals in the SCIE, with the Customize option clicked and highlighted, shows a pop-up of other impact, normalized, and source metrics to include on a comparison table
 

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