Medicare terms

Learn more about Medicare. Start with these definitions.



A deductible is an established out-of-pocket payment a Medicare enrollee must pay before his or her insurance begins taking over payment of the particular health care expense.

denial of coverage

Denial of coverage refers to a situation in which Medicare refuses to pay for certain medical services.

detailed explanation of non-coverage (DENC)

When a provider – a home health agency, or skilled nursing facility, or other agency – determines you are no longer eligible for Medicare services, you will receive a detailed explanation of non-coverage.

detailed notice of discharge

A detailed notice of discharge provide a full explanation of the reasons for your hospital discharge and/or why services you are receiving are no longer covered by Medicare.


Determination refers to a decision by Medicare to deny your claim, pay part of your claim or pay it in full.

disabled enrollee

A disabled enrollee is a person under 65 who qualifies for Medicare because of a disability, or is receiving benefits through Social Security or the Railroad Retirement system.

donut hole

Medicare’s “donut hole” refers to the coverage gap in your Medicare Part D prescription drug benefit — the point where your prescription drug expenses exceed the initial coverage limit of your plan, but have not yet reached the catastrophic coverage level.

When Medicare Part D was first introduced, patients paid 100 percent of their drug costs while in the donut hole (as opposed to 25 percent before the donut hole, and 5 percent after the donut hole). The Affordable Care Act included a provision to close the donut hole by 2020, and the percentage of costs that enrollees pay while in the donut hole has been steadily shrinking since 2011. In 2018, while in the donut hole, enrollees pay 35 percent of the cost of brand-name drugs and 44 percent of the cost of generic drugs.

The Bipartisan Budget Act of 2018 is closing the donut hole one year early for brand-name drugs, so enrollees will pay just 25 percent of the cost of brand-name drugs starting in 2019. By 2020, the donut hole will also be eliminated for generic drugs, and enrollees will pay 25 percent of all drug costs until they reach the catastrophic coverage level.

Before 2019 (and before 2020 for generic drugs), when you reach the donut hole, you’ll no longer have a 25 percent coinsurance payment (or similar copay, if that’s how your plan is designed) and will instead begin paying more of your costs. In 2018, you enter the donut hole when the total cost of your drugs (including the part you pay and the part your plan pays) reaches $3,750. Note that you will have paid much less than this amount out-of-pocket, because your drug plan will have picked up the majority of the cost.

You reach the catastrophic coverage level (ie, get out of the donut hole) after your costs reach $5,000 in 2018, including your deductible (which can be no more than $405 in 2018), copays/coinsurance, and the manufacturer discount for brand-name drugs that you receive while in the donut hole. In 2018, the manufacturer’s discount is 50 percent on brand-name drugs while you’re in the donut hole. You’re paying 35 percent, the drug plan is paying 15 percent, and the manufacturer’s discount is 50 percent. The portion you pay and the portion covered by the manufacturer’s discount (a total of 85 percent in 2018) counts towards getting you to that $5,000 mark. For generic drugs, only the 44 percent that you pay counts towards reaching the $5,000 upper limit of the donut hole.

Once you come out the other side of the donut hole and reach the catastrophic coverage level, your plan pays most of your prescription drug expenses through the end of the year, leaving you with minimal copays or coinsurance. At this coverage level, your prescription costs for the rest of 2018 are limited to the greater of 5 percent coinsurance, or copays that amount to $3.35 for generics and preferred multi-source drugs, and $8.35 for other brand-name drugs.

dual eligible

Americans who are enrolled in both Medicaid and Medicare are referred to as dual-eligible beneficiaries, or Medicare dual eligibles, or sometimes simply duals.

Dual-eligibles are enrolled in both programs when a Medicare enrollee’s income and assets are low enough to qualify them for Medicaid help in paying for some of the costs of Medicare – or to qualify them for full coverage under both Medicare and Medicaid.

These enrollees are commonly broken into two groups:

  • full-benefit dual-eligibles – who have Medicare but also receive benefits under Medicaid
  • partial duals – who have Medicare but qualify to have Medicaid help pay for expenses such as Medicare premiums and/or cost-sharing

Read more about dual eligibles.

durable medical equipment

Durable medical equipment is a class of Medicare-approved equipment authorized by an enrollee’s physician. Examples include wheelchairs, hospital beds, and oxygen equipment .

durable power of attorney

Durable power of attorney refers to your formal designation of a person to advocate on your behalf and make decisions about your personal affairs in the event you become unable to make decisions yourself.

Medicare Advantage open enrollment period

The Medicare Advantage open enrollment period is available starting in 2019. It runs from January 1 to March 31 and allows Medicare Advantage enrollees to either switch to Original Medicare (plus a Part D plan if they want one) or to switch to a different Medicare Advantage plan. Enrollees can only make one such change during the open enrollment period (as opposed to the annual election period in the fall, when people can change their minds multiple times).

Learn more about the Medicare Advantage open enrollment period.