A growing share of Americans got health insurance as sign-up season for President Barack Obama's health care law neared its end last month, a major survey released Monday has found.
The Gallup-Healthways Well-Being Index provides independent validation for White House claims that the law is expanding access, particularly for working people with no health coverage on the job. But the improvement, while substantial, doesn't appear as large as some of the numbers claimed by the law's supporters.
Gallup found that the share of adults without health insurance shrank from 17.1 percent at the end of last year to 15.6 percent for the first three months of 2014.
The decline would translate roughly to more than 3.5 million people gaining coverage. The trend accelerated as the March 31 enrollment deadline loomed.
"The Affordable Care Act, commonly referred to as 'Obamacare,' appears to be accomplishing its goal of increasing the percentage of Americans with health insurance," said Gallup's analysis of the findings.
The survey is important because it combines the quick turnaround of media polls with extensive outreach usually seen in government research. Gallup interviewed more than 43,500 adults, or more than 40 times the number in a typical national media poll.
The administration says more than 7 million have signed up for subsidized private plans through new insurance markets. Additionally, 3 million previously uninsured people gained coverage through the law's Medicaid expansion for the poor.
However, the administration's numbers are not comparable with Gallup's.
The White House figure of 7 million-plus insurance exchange sign-ups includes insured people who switched their previous coverage, as well as people who have not paid their first month's premium, and who would therefore still be uninsured.
Also, Gallup is counting just adults, while the administration figures include children as well.
"This survey and other independent analyses highlight a historic expansion in coverage," said Aaron Albright, a spokesman for the Health and Human Services department.
It may take much of the rest of the year to get a true picture of the health care law's impact on coverage.
Gallup found the biggest insurance gains were among lower-income people and among African-Americans.
African-Americans saw their uninsured rate drop by 3.3 percentage points.
Latinos remained more likely than any racial or ethnic group to lack access, with 37 percent uninsured.
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