The Nature Index is a database of author affiliations and institutional relationships. The Index tracks contributions to research articles published in 82 high-quality natural-science journals, chosen 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 Research.

Nature Index metrics

The Nature Index uses Count and Share to track research output. A country/region or an institution is given a Count of 1 for each article that has at least one author from that country/region 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/regions or institutions.

To glean a country’s, a region’s or an institution’s contribution to an article, and to ensure 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 then 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/regions, although complicated by the fact that some institutions have overseas labs that will be counted towards host country/region totals.

Adjusted Share accounts for the small annual variation in the total number of articles in the Nature Index journals. It is arrived at by calculating the percentage difference in the total number of articles in the Index in a given year relative to the number of articles in 2019 and applying this adjustment to Share values.

NATUREINDEX.COM

natureindex.com users can search for specific institutions or countries and generate their own reports, ordered by Count or Share.

Each query will return a profile page that lists the country or institution’s recent outputs, from which it is possible to drill down for more information. Articles can be displayed by journal, and then by article. Research outputs are organized by subject area. The pages list the institution or country/region’s top collaborators, as well as its relationship with other organizations. Users can track an institution’s performance over time, create their own indexes and export table data.

This supplement

The Nature Index 2020 South Korea supplement provides listings according to the research outputs of countries and institutions. The data on which these listings are based were extracted from the Nature Index database for the period between 1 January 2015 and 31 December 2019. The research outputs in the 82 journals selected by Nature Index were tracked on both the country and institution levels.