The Affordable Care Act has helped 16.4 million uninsured people gain health coverage, but roughly half of Americans don’t support the law. Misinformation is a big reason why, according to new research released today at the American Public Health Association’s 143rd Annual Meeting in Chicago.

Researchers examined data from the 2013 Douglas County (Nebraska) Community Health Survey, which included four questions about the ACA. Of the nearly 500 responses, 56.7 percent did not answer correctly to more than one question and only 4 percent answered all four questions correctly. Moreover, misconception of the ACA increased the likelihood of negative perception of the law by 73 percent.

“The findings are timely in consideration of the approaching presidential election and ongoing debate of ACA,” said Dejun Su, PhD, lead researcher and associate professor at University of Nebraska Medical Center. “Our study is unique in that it was based on a population-based, random sample survey —whereas most other findings on this topic were based on polls that lacked information or in-depth analysis.”

Women, Hispanics and people with poor self-rated health were more likely to answer the questions incorrectly. Conversely, people who were uninsured or well-educated were more likely to answer the questions correctly.

Overall, 56 percent of the respondents believed that the ACA negatively impacts U.S. health care.

“Increasing public support for the ACA calls for significant educational effort to alter misconceptions of the ACA, especially among females, Hispanics and people with poor health,” Su said.