People are so confused about the costs covered by their health insurance that they're avoiding medical treatment, according to a new survey.

The survey found that 27% of respondents avoided medical care or treatment because they were unsure of what their insurance covered, according to a survey released today by Policygenius, an online insurance marketplace.

Consumer confusion about health insurance seems to be getting worse, the survey said.

The annual survey found that more than 85% of respondents didn't know the basic benefits that health insurance plans must cover under the Affordable Care Act, up from 80% in 2018 and 78% in 2017.

"The survey data suggest the reason people avoid care is because they don't fully understand their insurance coverage and would rather avoid a surprise bill," said Myles Ma, health care expert at Policygenius, in a prepared statement.

Also, only 29.3% of respondents were able to correctly explain the definition of premiums, copays and deductibles, which are the most common health-care expenses, and only 36% of those who have health insurance could define all three terms.

These were among the other survey findings:

• Only about 12% of respondents knew the correct 2019 ACA open enrollment dates.
• Only 22% knew aid is available to purchase Obamacare health-care coverage. Of those without health insurance, only 15.6% knew this.
• Eighty percent of people mistakenly believe there is still a tax penalty for going without health insurance.
• Thirteen percent of respondents didn't know if they had health insurance.

The report was based on a survey of a nationally representative group of 1,500 U.S. adults earlier this month through Google Consumer Surveys, Policygenius said.