With millions of people responsible for their own and their family’s health insurance, it’s extremely important that subscribers of any health plan know exactly what type of care they’re getting, but it seems that the majority of people haven’t the slightest clue about the most basic insurance terminology, according to a new study.

“I have a PhD in economics and I’ve spent a bunch of time giving insurance companies feedback about policies, and I still find them difficult to understand,” George Lowenstein, a health care economist and author of the study, told The Washington Post. “I assumed that extrapolating from myself that the average American individual would have an even lower understanding.”

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Lowenstein was right. He surveyed 202 people who had employer-sponsored health insurance, asking them to define four of the most basic terms of health insurance: copayment, deductible, out-of-pocket maximum, and co-insurance. You can see the questions below.

Over 90 percent of participants believed they understood each concept, except for co-insurance, which 57 percent thought they understood. But only 14 percent of participants were able to actually define the terms.

Lowenstein continued his experiment, and gave all of the participants a hypothetical insurance plan, in which they had to calculate their total costs for a four-day stay in a hospital. Only 11 percent were able to figure out the price, and 14 percent were within $1,000.

“It is strange, in my opinion, that the insurance market has evolved so, that so few individuals understand the fundamentals of the medical insurance plans they are insured under,” Lowenstein said in a statement.

Consumers are offered so many different incentives to choose different types of plans, but Lowenstein says that it will be difficult for them to understand what their best choices are if they don’t “understand the most basic elements of plan design,”

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This can be a huge problem when the Affordable Care Act’s insurance exchanges become operational and start offering a wide range of options on Oct. 1. However, as health insurance companies begin to advertise, some believe consumers will become more accustomed to the terminology, according to Forbes.

“It is complicated, talks about topics that most people don’t understand and has been ‘demagogued,’ which adds to the confusion,” Helen Darling, president and chief executive officer of the National Business Group on Health, told Forbes. “Also, it is a mistake to communicate some things too early because people get confused if they learn about something before they can act on something.”

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Companies are now mandated to include summaries of benefits with their plans. These will also include definitions of the terms above, however, Lowenstein is still unsure people will understand the complexity. He says that the ideal thing to do would have been to simplify coverage, and get rid of all the extra cost-sharing policies, only keeping co-payments.

“It’s possible that an all co-pay plan can be kind of scary because what you see is what you get,” Loewenstein told The Washington Post. “Some of the prices are high, of course. But in a traditional plan you’re paying the same prices. You just aren’t as clear about it.”

Take the quiz below to see how well you understand health insurance terminology. The answers are available below.

A. Which of the following describes an (in-network) Out-of-Pocket Maximum? Assume that all the responses refer to in-network expenses.

  1. After meeting the out-of-pocket maximum, all medical expenses are covered 100%
  2. After meeting the in-network out-of-pocket maximum, copays must still be paid, but all other medical expenses are covered 100%
  3. After meeting the out-of-pocket maximum, yo must pay 100% of your medical expenses
  4. I'm not sure

B. Which of the following best describes Coinsurance?

  1. A specified dollar amount you pay for a specific service
  2. The total amount you are required to pay until you reach your deductible
  3. The percent of the cost of medical services that the insurer pays
  4. The amount your employer contributes to paying for your health premium
  5. I'm not sure

C. Which of the following best describes a Copay?

  1. The specific dollar amount you pay for a specific service
  2. A specific dollar amount your insurer pays for a specific service
  3. A fixed percent of the cost of a procedure that you have to pay (the insurer pays the remainder)
  4. The amount your employer contributes to paying for your health premium
  5. I'm not sure

D. Which of the following best describes a Deductible?

  1. The amount deducted from your paycheck to pay for your insurance premium
  2. The amount deducted (covered) out of your total yearly medical expenses
  3. The amount you pay before your insurance company pays benefits
  4. The amount you pay before your health expenses are covered in full
  5. I'm not sure
definitions Washington Post