China overtakes United States on contribution to research in Nature Index

For the first time, China has overtaken the United States as the number one ranked country or territory for contributions to research articles published in the Nature Index group of high-quality natural-science journals.

Data on author affiliations from the 82 journals tracked by the Nature Index show that China had a Share of 19,373 from January to December 2022, compared with 17,610 for the United States (see ‘Role reversal’).

A country’s Share takes into account the percentage of authors from that nation on each paper published in Nature Index journals; an article published entirely by China-based researchers would yield a Share of 1 for China.

Since the Nature Index was first introduced in 2014, China’s Share has been rapidly gaining ground, and it was the leading country in the physical sciences and chemistry in 2021.

The latest data — a snapshot of the database taken in April, ahead of the full release of 2022 data in the 2023 Nature Index annual tables — suggest that China also overtook the United States in Earth and environmental sciences for the first time. This leaves only one natural-sciences category — life sciences — in which it is still trailing.

Shifting balance

Different measures of scientific performance have been pointing to a shift in the national balance of global science since the mid-2010s: a 2018 US National Science Foundation data set showed that China published the largest number of papers, for example.

The focus in the past five years has been on when China might overtake the United States on metrics that attempt to measure quality, such as assessments of citation numbers.

For instance, a 2022 report by Japan’s National Institute of Science and Technology Policy used fractional counting, or the percentage of authors from a given country on a paper, to determine contributions to highly cited research. It found that, between 2018 and 2020, Chinese research comprised more of the top 1% of the most frequently cited papers than did US research.

Although the Nature Index does not assess citations, it tracks journals, selected by an independent group of actively publishing researchers, that are intended to represent a consensus of the upper echelon of journals in the natural sciences. (Nature Index’s news and supplement content is editorially independent of its publisher, Springer Nature.)

Caroline Wagner, a science and policy researcher at the Ohio State University in Columbus, who has published research1 suggesting that China has overtaken the United States on top-cited papers, says that, when measured on “simple bibliometrics like productivity and citations, China has outperformed expectations”.

She adds, however, that it still “significantly trails” behind other nations “in its capacity to absorb and apply knowledge”, and that the impact of the decline in its research collaborations with some major countries, such as the United States, remains uncertain.