Four Chinese scientific institutions ranked among world's top 10 institutions of research output in 2021, with the country demonstrating strong R&D capacity and gradually minimizing the gap between developed countries, according to the Nature Index released in June.

Chinese Academy of Sciences won the first spot globally, followed by Harvard University in US, Max Planck Society in Germany and France's French National Centre for Scientific Research.

University of Chinese Academy of Sciences ranked eighth, rising from 13th last year. University of Science and Technology of China and Peking University came in at No 9 and No 10, respectively.

China's investment into research paid off, according to Nature, and experts said the country's strong scientific performance is likely to be sustained over the coming years.

As an open database of author affiliations and institutional relationships, the Nature Index tracks contributions to research articles published in 82 high-quality natural-science journals, chosen based on reputation by an independent group of researchers.