What is Category Normalised Citation Impact (CNCI) and how can I use it?
Answer
What is CNCI?
Category Normalised Citation Impact (CNCI) is a field-normalised metric developed by Clarivate. It compares the citation performance of a publication to others of the same document type, publication year, and subject category (e.g. field or subfield).
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A CNCI of 1.00 means a publication has received the expected number of citations.
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A score above 1.00 means it has been cited more than expected.
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A score below 1.00 means it has been cited less than expected.
For example, a CNCI of 2.0 means the paper has been cited twice as often as similar publications.
Why is CNCI useful?
CNCI is particularly helpful because it:
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Enables fair comparison across disciplines
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Takes into account differences in publication type and age
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Helps identify influential outputs
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Provides context for citation impact in evaluation exercises
It supports responsible metrics use by avoiding misleading raw citation comparisons across fields with different citation patterns.
How is CNCI Calculated?
The CNCI is calculated by dividing the actual number of citations received by a publication by the expected number of citations in the same category. The expected citation count is based on global averages for papers of the same type, age, and subject category (e.g. physics article published in 2021).
The formula for CNCI is:
- CNCI > 1.00 indicates that the paper has received more citations than expected for its field.
- CNCI = 1.00 means the paper has received the expected number of citations for its field.
- CNCI < 1.00 means the paper has received fewer citations than expected for its field.
How can CNCI be used responsibly?
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Research Evaluation: CNCI is commonly used by institutions, funding bodies, and journals to assess the impact of research. Researchers can (with care) use CNCI to benchmark their own work and evaluate the collective impact of their research output.
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Institutional and National Rankings: CNCI is often used in institutional and national rankings to compare the research performance of universities and research organisations. It helps to identify institutions that produce highly impactful research, relative to their peers.
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Grant and Promotion Applications: CNCI can serve as evidence of research impact in applications for grants, promotions, or tenure. A high CNCI can be an indicator of a researcher’s or institution's strong academic performance, showing that their work has had a significant impact compared to others in their field.
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Identifying trends: Track CNCI over time to assess whether research influence is growing or shifting in certain areas.
Please note that CNCI is not a measure of quality or significance on its own. It should always be used alongside qualitative evidence and additional metrics to support fair, responsible evaluation.
Where can I find CNCI data?
Web of Science:
Web of Science displays CNCI at the article level (when available), helping researchers understand how individual papers perform relative to field averages.
InCites provides deeper analysis of CNCI across:
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Individual researchers
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Departments and institutions
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Countries or fields of research
It also includes Collab-CNCI, a variant metric that shows the impact of collaborative research compared to expected norms.
How to find CNCI in Web of Science and InCites
To find CNCI data for a specific paper, author, or institution in Web of Science, follow these steps:
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Log In to Web of Science using the link available via Library Search:
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Search for the Paper or Author:
- You can search by the title of a paper, the name of an author, or the name of an institution to find citation data.
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Review the CNCI Information:
- Once you have found the relevant paper or author, look at the citation overview for the CNCI score. If CNCI is available, Web of Science will display the value, indicating how the paper or author compares to the average citation count in their field.
- Once you have found the relevant paper or author, look at the citation overview for the CNCI score. If CNCI is available, Web of Science will display the value, indicating how the paper or author compares to the average citation count in their field.
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Use InCites for Further Analysis:
- For a more detailed analysis of CNCI at the institutional or author level, you can access InCites. It offers tools to examine CNCI data in the context of larger datasets, enabling benchmarking against other researchers or institutions.
- For a more detailed analysis of CNCI at the institutional or author level, you can access InCites. It offers tools to examine CNCI data in the context of larger datasets, enabling benchmarking against other researchers or institutions.
Further reading
For more details on CNCI, including how it is calculated and how to use it, you can refer to Clarivate’s detailed guide on CNCI in Web of Science and InCites: