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Glossary - I

This glossary explains terms in the Medicare program.


Independent reviewer

An organization (sometimes called an Independent Review Entity or IRE) that has no connection to your Medicare health plan or Medicare Prescription Drug Plan. Medicare contracts with the IRE to review your case if you appeal your plan's payment or coverage decision or if your plan doesn't make a timely appeals decision.

Initial coverage limit

Once you've met your yearly deductible, you'll pay a copayment or coinsurance for each covered drug until you reach your plan's out-of-pocket maximum (or initial coverage limit). You'll then enter your plan's coverage gap (also called the "donut hole").


Doctors, hospitals, pharmacies, and other health care providers that have agreed to provide members of a certain insurance plan with services and supplies at a discounted price. In some insurance plans, your care is only covered if you get it from in-network doctors, hospitals, pharmacies, and other health care providers.

Inpatient care

Health care that you get when you're admitted to a health care facility, like a hospital or skilled nursing facility.

Inpatient hospital care

Treatment you get in an acute care hospital, critical access hospital, inpatient rehabilitation facility, long-term care hospital, inpatient care as part of a qualifying research study, and mental health care.

Inpatient hospital services

Services you get when you're admitted to a hospital, including bed and board, nursing services, diagnostic or therapeutic services, and medical or surgical services.

Inpatient prospective payment system (IPPS)

Hospitals that have contracted with Medicare to provide acute inpatient care and accept a predetermined rate as payment in full.

Inpatient rehabilitation facility

A hospital, or part of a hospital, that provides an intensive rehabilitation program to inpatients.

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This glossary explains terms in the Medicare program, but it isn't a legal document. The official Medicare program provisions are found in the relevant laws, regulations, and rulings.