It might seem obvious that poor people benefit when they get health insurance. But, as The New York Times reports, there actually is a serious debate among economists and policymakers about whether it pays off for government to provide coverage to the poor.

Now, however, the answers may be coming into clearer focus.

In a ground-breaking study, researchers have documented that low-income people who start receiving Medicaid insurance get more care, including preventive checkups, and indicate that they feel better and wind up in better shape financially than those who lack health coverage.

“There has been a lot of genuine uncertainty about whether it makes a difference when you give people Medicaid,” Amy Finkelstein of M.I.T., who led the study with a fellow economist from Harvard University, said in a news release. “The short answer from our study is that it does.”

The findings could be influential because, as The Wall Street Journal notes, in 2014 the nation’s health care overhaul is due to bring  coverage to many more Americans. The study also comes as some financially squeezed states are reducing Medicaid benefits for the poor.

A rare opportunity for researchers to evaluate how otherwise comparable groups of people fared with, or without, health insurance came up in Oregon. In 2008, the state expanded its Medicaid program to include 10,000 more uninsured people but nearly 90,000 applied, prompting the state to choose the participants by lottery.

That gave the researchers the chance to compare what happened with insured, versus uninsured, Oregonians during the period before the state found a way to provide Medicaid to all of the applicants.

The researchers found that the Medicaid-covered group was roughly:

  • 35 percent more likely to go to a clinic or see a doctor.
  • 20 percent more likely to have a cholesterol check.
  • 60 percent more likely, among the women, to have mammograms.
  • 25 percent more likely to report having good or excellent health.
  • 40 percent less likely to say that their health had worsened in the past year.
  • 25 percent less likely to have an unpaid medical bill sent to collections.