Press release

Japan slows decline in research output as global collaboration helps Big 5 science superpowers consolidate positions as world leaders

15 March 2022

With access to the biggest budgets, world-class facilities and a long history of scientific excellence, the leading five countries in the Nature Index are the linchpins of the global research system

Tokyo March 15, 2022

The Nature Index 2022 Big 5, published on March 9, 2022 in Nature, shows that the leading five countries by Share in the Nature Index (The United States, China, Germany, the United Kingdom and Japan) remain unmoved since 2015. Together these five countries were responsible for 69.4% of the total Share in the Index for the period 2015–21*

Though the overall order of the Big 5 remains consistent, China has seen a massive increase in output which translates to an 81% change in adjusted share from 2015 to 2021. This reflects China’s growth in the physical sciences and chemistry, with China overtaking the United States in physical sciences for the first time in 2021, achieving a 24% global share in the subject, with the United States at 23.8%.

Institutions from China and the United States are dominant in the Index, with 42 of the Top 50 leading institutions coming from one of the two countries, 16 from China and 26 from the United States respectively. Seven of the Top 100 leading institutions come from Japan. The United States continues to dominate the life sciences, with 44% of the global Share, which makes up 48.5% of their overall Share by subject. Institutions with the biggest Share increase for each of the Big 5 countries are highlighted, with the Okinawa Institute of Science and Technology Graduate University (OIST) showing the biggest Share increase in Japan.

Speaking on the Big 5 Index, David Swinbanks, founder of the Nature Index, said: “This supplement allows us to look at the stand-out research initiatives in each of the United States, China, Germany, United Kingdom and Japan across the natural sciences disciplines.

“It highlights each country’s discipline strengths with a focus on which institutions and people are driving change for the better at the leading edge of global science, and what they are doing to share and spread their success through collaboration and other means.

“Institutions are continuing to demonstrate the resilience, adaptability and innovation of the research sector, with great advancements in science on display. It is clear from the features in the supplement there has been no slowdown in output, particularly evident from the increase in China’s chemistry output. Japan’s decline in output appears to be arresting and in fact showed a slight rise in 2020.”

Analysis of global collaboration based on the collaboration score (CS) of the Nature Index shows that the strongest relationships are within the Big 5 group, although Germany, the United States and the United Kingdom are all collaborating more with France than they do with Japan. The three strongest pairings of international institutions are shown for the leading five countries, where the University of Tokyo in Japan has strong partnerships with the Max Planck Society (Germany), and the French National Centre for Scientific Research (France), which are prolific collaborators, as well as with the Chinese Academy of Science (China).

The supplement also highlights Japan’s international partnership projects, such as the International Ocean Discovery Program led by Japan Agency for Marine-Earth Science and Technology (JAMSTEC) and the T2K Collaboration, a Japan-based particle-physics experiment, with the Hyper-Kamiokande based in the University of Tokyo. The supplement suggests that strengthening Japan’s international research collaborations and targeted funding for prestigious institutions could be important factors in stopping its decline in its research output. Japan’s adjusted Share had dropped by 19.1% in 2015-2021, although this decline, which is the largest among the leading five countries in the Index, has slowed since 2019.

In addition, five researchers, each based in one of the five leading countries in the Nature Index, are also featured, including Dr. Ayuko Hoshino, a molecular biologist at the Tokyo Institute of Technology, who studies exosomes, which are minute vesicles that are secreted by almost every type of cell in the human body. In 2020, Dr. Hoshino was awarded the Award for a Brilliant Female Researcher by the Japan Science and Technology Agency (JST), where the award was launched in 2019 to promote the research of female scientists.

Note to Editors:

The full Nature Index Big 5 can be found at the Nature Index website, including a list of the leading 100 institutions from the United States, China, Germany, United Kingdom and Japan.

Share, Nature Index’s key metric, is adjusted to account for the small annual variation in the total number of articles in the Nature Index journals.

The Collaboration Score (CS) is calculated by adding each institutional partner’s Share in their joint articles in 2021*.

 * Data for 2021 represent the period October 2020–September 2021.

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 The database is compiled by Nature Portfolio part of Springer Nature.

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.

Nature Portfolio is a range of high-quality products and services across the life, physical, chemical and applied sciences – including journals, databases and researcher services – dedicated to serving the scientific community.

Nature (founded in 1869) is the leading, international weekly journal of science. Nature Portfolio also publishes a range of Nature-branded subscription journals, the leading open access multidisciplinary journal Nature Communications, other open access journals including Scientific Reports, and a range of Nature Partner Journals published in partnership with institutions and societies. Together, these journals publish some of the world's most significant scientific discoveries.

Online, provides over nine million unique visitors per month with Nature Research content, including news and comment from Nature, and the leading scientific jobs board, Nature Careers. Nature Portfolio also offers a range of researcher services, including online and in-person training and expert language and editing services. For more information, please visit and follow @NaturePortfolio. Nature Portfolio is part of Springer Nature.

For over 175 years Springer Nature has been advancing discovery by providing the best possible service to the whole research community. We help researchers uncover new ideas, make sure all the research we publish is significant, robust and stands up to objective scrutiny, that it reaches all relevant audiences in the best possible format, and can be discovered, accessed, used, re-used and shared. We support librarians and institutions with innovations in technology and data; and provide quality publishing support to societies. 
As a research publisher, Springer Nature is home to trusted brands including Springer, Nature Portfolio, BMC, Palgrave Macmillan and Scientific American. For more information, please visit and @SpringerNature

Ayako Miyazaki
Springer Nature
Corporate Affairs
TEL: +81-(0)3-4533-8204        


More Press Releases

PrivacyMark System