Despite the millions of people who have gained insurance coverage as a result of the health law, a survey released Thursday shows outreach efforts for two popular provisions are missing key parts of their target audience.

The Commonwealth Fund’s report on gaps in health insurance found that more than 60 percent of survey respondents know about a provision that allows children up to age 26 to stay on their parents’ insurance. Meanwhile, half know about the law’s high-risk insurance pools. For both of these provisions, though, a significant number of people likely to benefit remain in the dark.

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For example, 40 percent of respondents age 19 to 29 didn’t know about the benefit that permits those under 26 to obtain coverage from their parents’ plan. When asked about the high-risk pools, 45 percent of people in fair or poor health and 65 percent of people who were uninsured didn’t know about that coverage option.

“It’s indicative that there are differences in what people are hearing” about the law, said Sara Collins, a vice president of the Commonwealth Fund and one of the report’s authors. “There’s a need to get information to the people who will benefit.”

According to the survey, awareness of the health law’s provisions varied greatly depending on income. Fifty-four percent of respondents who had incomes below 250 percent of the federal poverty level were unaware of the under-26 provision, compared to just 25 percent at or above that line. For the high-risk pools it was 63 percent and 39 percent, respectively.

Both parts of the law address important gaps in coverage also highlighted by Thursday’s report. Among the more than 2,000 respondents, slightly more than a quarter went without insurance at some point in the year prior; 69 percent had gone without insurance for more than a year.

The under-26 provision has allowed 2.5 million young adults to gain coverage, according to a government report, and brought down the uninsured rate by a few percentage points. A recent analysis by Gallup, however, speculated that the young adult uninsured rate has hit a plateau since the health law took effect.

“There’s a robust level of awareness” for under-26 coverage, said Jennifer Mishory, deputy director for Young Invincibles, a pro-health law group focused on young adults. She added that gaps in awareness can largely be attributed to traditionally underserved, uninsured groups that are less engaged in health insurance.

Case in point: the Hispanic population, which the survey found had much less knowledge of the health law’s coverage expansions. Thirty-eight percent were aware of the under-26 provision and 28 percent for the high-risk pools, compared with 71 percent and 57 percent, respectively, among white respondents.

Mishory said that Young Invincibles is looking to partner on outreach with community health centers, which address uninsured populations, as well as develop a smartphone application to spread awareness. The group is also in the middle of a nationwide bus tour.

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“We need to do more,” said Kathleen Stoll, director of health policy for Families USA, a group that supports the health law. She described how “it takes a while for programs like these to break through.” People with pre-existing conditions are a particular challenge, because individual states run the high-risk pools with varied levels of publicity.

And in a surprise, as Stoll noted, Republicans showed greater awareness than Democrats for the health law provisions: 74 percent versus 65 percent for the under-26 rule, and 60 percent versus 52 percent for high-risk pools.

The poll, conducted by Knowledge Networks for the Commonwealth Fund, surveyed 2,134 adults between June 24 and July 5, 2011 and has a margin of error of +/- 3 percent.

This article was reprinted from kaiserhealthnews.org with permission from the Henry J. Kaiser Family Foundation. Kaiser Health News, an editorially independent news service, is a program of the Kaiser Family Foundation, a nonpartisan health care policy research organization unaffiliated with Kaiser Permanente.