A web-based insurance broker says it has proof that many U.S. adults are just pretending to understand their health coverage.

PolicyGenius, the New York City-based owner of an insurance quote site by that name, commissioned a survey of 2,022 U.S. adults who were either in charge of their household’s health coverage or shared responsibility for health coverage with another adult.

All participants included in the final results had used their health coverage within the past year.

The survey team asked the participants whether they understood several common health insurance terms, then asked the participants to define the terms.

The share who said they definitely understood the terms was 83 percent for “co-pay,” 74 percent for “deductible” and 47 percent for “coinsurance.”

Related: ACA definitions: Enrollment period basics

Just 50 percent could actually define “co-payment.” Fifty-two percent could define “co-pay.” Only 22 percent knew that “coinsurance” is the percentage of a covered bill the coverage holder pays after a deductible or other threshold is reached and before the out-of-pocket spending maximum applies.

Just 4 percent of the survey participants included in the results could define all four terms correctly, PolicyGenius says.

Only 36 percent of the Millennials surveyed could define any of the four terms correctly.

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Consumers flunk health plan choice test

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