A large proportion of recent immigrants, both legal and illegal, are low-skilled workers and about one-third of those have not completed high school, giving them significantly less education than Americans born in the United States, according to the study, which is based on census data as recent as March of this year.

The survey focuses on public costs associated with the new generation of immigrant workers. It does not, however, analyze contributions they make by paying taxes and taking undesirable, low-income jobs — an omission criticized by some immigration scholars.

Still, the survey provides a panorama of the effects of immigration since 2000.

About 30 percent of all immigrants and their children lack health insurance, Mr. Camarota reports, compared with 13 percent of native-born Americans. One of every three uninsured people in the country is an immigrant or a young American-born child with at least one immigrant parent, he found. Immigrant families account for almost three-quarters of the increase in the uninsured in the past 15 years, he concludes.

Immigrants are employed at higher rates than Americans, according to the survey. But because of their low educational levels, many work in low-paying, entry-level jobs that do not provide health insurance or other benefits.

“Immigrants have had an enormous impact on the lack of health insurance,” Mr. Camarota said. “If we are going to have a debate about health insurance, we should recognize that most of the growth in the uninsured comes from recently arrived immigrants and their American-born kids.”