  China's rising in scientific research output is impressive. The academic
community is curious about the time when the cross-over in the number of annual
scientific publication production between China and the USA can happen. By
using Web of Science Core Collection's Science Citation Index Expanded
database, this study finds that China still ranks the second in the production
of SCI-indexed publications in 2019 but may leapfrog the USA to be the first in
2020 or 2021, if all document types are considered. Comparatively, China has
already overtaken the USA and been the largest SCI-indexed original research
article producer since 2018. However, China still lags behind the USA regarding
the number of review paper production. In general, quantitative advantage does
not equal quality or impact advantage. We think that the USA will continue to
be the global scientific leader for a long time.
