Mon Mar 16, 2015 10:12am EDT

Thirty percent of adults in the United States have taken steps to hide their information from government surveillance programs monitoring phone and electronic communications, a Pew Research Center survey said on Monday.

About a quarter, or 22 percent, said they had changed use of various technology platforms “a great deal” or “somewhat” since Edward Snowden, a former National Security Agency contractor, disclosed the surveillance programs in mid-2013, the Pew survey showed.

"We find that a portion of the population is adjusting some activity at least in some simple ways like changing their privacy settings and being a bit more discreet in the things they say and search for,” said Lee Rainie, director of Internet, science, and technology research at the Pew Research Center.

Eighty-seven percent of Americans have heard at least something about the monitoring programs, the survey showed.

Among that group, 17 percent said they had changed privacy settings on social media to shield information from the government.

Fifteen percent have avoided certain software applications, and 15 percent have used social media less often.

Fifty-seven percent of those surveyed said it was unacceptable for the government to monitor the communications of U.S. citizens.

But about four in five it was acceptable to monitor communications of suspected terrorists. Sixty percent said it was OK to monitor the communications of U.S. and foreign leaders.

Overall, 52 percent of Americans described themselves as “very concerned” or “somewhat concerned” about the government monitoring programs. Nearly half said they were “not very concerned” or “not at all concerned.”

Rainey was to release the findings in a presentation at the South By Southwest Conference in Austin, Texas.

The Pew survey comprised 475 adults and was carried out between Nov. 26, 2014, and Jan. 3. The sampling error is 5.6 percentage points.