China’s college boom has helped boost US postgraduate education and local economies in college towns, according to a new study.

The country’s massive higher education expansion – which lifted annual undergraduate enrolment in China from about 1 million in 1999 to 9.6 million by 2020 – resulted in waves of students going abroad and produced measurable effects inside US universities, according to a team at the National Bureau of Economic Research, a non-profit based in Cambridge, Massachusetts.

The study said that for every 100 graduates in China, about three or four went on to study in the US – most of them in science, technology, engineering and mathematics (STEM) master’s programmes – helping to fuel an expansion in related courses at American universities.

For every 100 Chinese master’s students, US universities added about one new STEM master’s programme, the study found.

The study appeared to contradict claims made by some American politicians that Chinese students were “crowding out” their US peers. Last year Vice-President J.D. Vance told Fox News that wealthy foreign students – “some Chinese oligarchs paying US$100,000 a year” – were taking places from “middle-class American kids from the heartland” at the country’s best universities.

But the researchers said the influx had helped create more places for American and other international students, describing the pattern as “crowding in”.

“Our results reveal a notable pattern of crowd-in effects. Each additional Chinese master’s student is associated with an increase of approximately 0.26 American master’s students,” the team wrote in their working paper, which has yet to be peer-reviewed.