16.9 million Americans gained health coverage under Affordable Care Act, study finds

Researchers estimate that from September 2013 to February 2015, 22.8 million Americans became newly insured and 5.9 million lost coverage, for a net of 16.9 million newly insured Americans.

Among those newly gaining coverage, 9.6 million people enrolled in employer-sponsored health plans, followed by Medicaid (6.5 million), the individual marketplaces (4.1 million), nonmarketplace individual plans (1.2 million) and other insurance sources (1.5 million).

The study also estimates that 125.2 million Americans -- about 80 percent of the nonelderly population that had insurance in September 2013 -- experienced no change in the source of insurance during the period, according to findings published online by the journal Health Affairs.

"The Affordable Care Act has greatly expanded health insurance coverage, but it has caused little change in the way most previously-covered Americans are getting health insurance coverage," said Katherine Carman, the study's lead author and an economist at RAND, a nonprofit research organization. "The law has expanded coverage to more Americans using all parts of the health insurance system."

The RAND study estimates 11.2 million Americans are insured through new state and federal marketplaces created under the Affordable Care Act, including 4.1 million who are newly covered and 7.1 million people who transitioned to marketplace plans from another source of coverage.

In addition, among the 12.6 million Americans newly enrolled in Medicaid, 6.5 million were previously uninsured and 6.1 million were previously insured.

The RAND study is the first to examine insurance transitions since the end of the second open enrollment period under the Affordable Care Act.

It analyzes information from the RAND Health Reform Opinion Study, a survey that has followed a representative sample of about 1,600 Americans aged 18 to 64 from September 2013 through February 2015. Participants are questioned periodically about whether they have health insurance, their source of insurance and other related questions.

None of the other surveys with equally current data on changes in coverage caused by the Affordable Care Act provide longitudinal information about coverage transitions, and none of the other longitudinal surveys are as current.

RAND researchers say the findings that the biggest gain in coverage was from employer-sponsored insurance runs counter to predictions that many employers may quit offering insurance in response to the Affordable Care Act and suggests that regardless of whether that occurs, employer-sponsored coverage will remain the nation's major source of health insurance coverage.

Other study findings include:

--Most of the gain in the number of Americans with insurance occurred between September 2013 and May 2014, reflecting the first open enrollment period.

--Coverage through individual nonmarketplace policies declined by 1.9 million and coverage from other sources (Medicare, military insurance and state programs) declined by 10 million over the study period.

--An estimated 24.6 million Americans moved from one source of insurance to another source of coverage during the study period.