A guide to the Nature Index

The Nature Index is a database of author affiliations and institutional relationships that tracks contributions to research articles published in high-quality natural-science and health-science journals selected by an independent group. It provides absolute and fractional counts of article publication at institutional and national levels, serving as an indicator of global high-quality research output and collaboration. Data are updated regularly, with the most recent 12 months available under a Creative Commons licence. The index uses Count and Share. Count assigns 1 to each country/territory or institution appearing on an article, regardless of author number, allowing the same article to count multiple entities. Share provides fractional attribution by dividing 1 across authors, splitting further across multiple affiliations, and summing author shares per institution and country/territory, including handling overseas labs.

"The Nature Index is a database of author affiliations and institutional relationships. The index tracks contributions to research articles published in high-quality natural-science and health-science journals, chosen based on reputation by an independent group of researchers. The Nature Index provides absolute and fractional counts of article publication at the institutional and national level and, as such, is an indicator of global high-quality research output and collaboration. Data in the Nature Index are updated regularly, with the most recent 12 months made available under a Creative Commons licence at natureindex.com. The database is compiled by Nature Portfolio."

"The Nature Index uses Count and Share to track research output. A country/territory or an institution is given a Count of 1 for each article that has at least one author from that country/territory or institution. This is the case regardless of the number of authors an article has, and it means that the same article can contribute to the Count of multiple countries/territories or institutions."

"To glean a country's, territory's, region's or an institution's contribution to an article, and to ensure that they are not counted more than once, the Nature Index uses Share, a fractional count that takes into account the share of authorship on each article. The total Share available per article is 1, which is shared among all authors under the assumption that each contributed equally. For instance, an article with 10 authors means that each author receives a Share of 0.1."

"For authors who are affiliated with more than one institution, the author's Share is split equally between each institution. The total Share for an institution is calculated by summing the Share for individual affiliated authors. The process is similar for countries/territories, although complicated by the fact that some institutions have overseas labs that will be counted towards host count"

Read at Nature