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Dimensions Analytics - research analytics database: Metric indicators & API

Search and analyze millions of research publications connected by more than 1.3 billion citations, Altmetric data, supporting grants, datasets, clinical trials, patents and policy documents.

Publication impact metrics

What is the RCR? How is the RCR score calculated?

The Relative Citation Ratio (RCR) is a citation-based measure of scientific influence of a publication. It is calculated as the citations of a paper, normalized to the citations received by NIH-funded publications in the same area of research and year.

The area of research is defined by the corpus of publications co-cited with the article of interest (the “co-citation network”) - it is therefore dynamically defined. In other words, the RCR indicates how a publication has been cited relative to other publications in its co-citation network and this is assumed to be reflective of the article’s area of research.

The RCR is calculated for all PubMed publications which are at least 2 years old. Values are centered around 1.0 so that a publication with an RCR of 1.0 has received the same number of citations as would be expected based on the NIH-norm, while a paper with an RCR of 2.0 has received twice as many citations as expected.

If you would like to see a detailed description of how the RCR is calculated, you can find this in the original publication. Another good overview of how the RCR works can be found here.

What is the FCR? How is it calculated?

The Field Citation Ratio (FCR) is a citation-based measure of scientific influence of one or more articles. It is calculated by dividing the number of citations a paper has received by the average number received by documents published in the same year and in the same Fields of Research (FoR) category.

The FCR is calculated for all publications in Dimensions which are at least 2 years old and were published in 2000 or later. Values are centered around 1.0 so that a publication with an FCR of 1.0 has received exactly the same number of citations as the average, while a paper with an FCR of 2.0 has received twice as many citations as the average for the Fields of Research code(s).

Compared to the Relative Citation Ratio (RCR), the FCR uses a more tangible definition of a field, i.e. you can get a list of all articles in a specific FoR code - the same is not possible for RCR where the a field is relative to the publication in question.

Fields of Research (FoR) is a classification system covering all areas of research from Arts and Humanities to Science and Engineering. Assigning FoR codes to publications in Dimensions is done automatically using machine learning emulations of the categorization processes. The FCR indicates how a publication has been cited relative to other publications with the same Fields of Research code(s).

How is the Altmetric Attention Score calculated?

The Altmetric Attention Score is a value that indicates the amount of attention received by an article across the internet. Sources that are being tracked include the mass media, policy documents, scholarly blogs, Wikipedia, open peer reviews, academic syllabi and a variety of social media, including Reddit, Twitter and Facebook. The diversity of the attention sources is represented by the mix of colors in the donut. The value is weighted according to how high profile the attention sources are: with news, blogs and policy papers ranking high, and social media much lower. The precise values can be found here.

Accessing the Dimensions API

Does Dimensions offer an API? If so, how do I access it?

Dimensions does offer an API. Visit this page to view documentation about the features and functionality of the Dimensions Search Language as it is used in the Dimensions API.