Economists have long cast some doubt on Chinese official figures, which show a huge economy that somehow manages to avoid the peaks and valleys that other countries regularly report. In recent years, China made efforts to improve that data by releasing more information more frequently, among other measures. It also gave its financial media greater freedom, even as censors kept a tight leash on political discourse.

But the party now sees reports of economic turbulence as a potential threat. The same goes for data.

“Many economic indicators are on a downward trend in China, and economic data has become quite sensitive nowadays,” said Yuan Gangming, a researcher at the Center for China in the World Economy at Tsinghua University.

The restrictions illustrate the Chinese government’s competing priorities, said Leland R. Miller, president of China Beige Book International, which surveys Chinese companies. “The environment is getting tougher and tougher to operate in,” he said, though he added that his company had not been told to rein in its activities.

“We are going to continue to see crackdowns on people telling a different story than what Beijing wants to hear,” Mr. Miller said. “At the same time, Beijing appears to be conflicted on this issue, because it recognizes that without independent gauges, commercial relations and foreign direct investment will suffer, due to growing skepticism over official data.”

Last September, Markit Economics, a British company, and Caixin Media, based in Beijing, stopped publishing preliminary results from a monthly survey of purchasing managers at Chinese factories. The preliminary results, which came a few days before the two firms and the government separately released complete numbers, often affected markets. As a result, officials at China’s statistics bureau objected to the early release, according to people with knowledge of the official order.

A spokeswoman for Markit declined to comment, while Caixin representatives did not respond to a request for comment.