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Medicare Primer

CRS Report for Congress
Prepared for Members and Committees of Congress
Medicare Primer
Patricia A. Davis, Coordinator
Specialist in Health Care Financing
Scott R. Talaga, Coordinator
Analyst in Health Care Financing
Cliff Binder
Analyst in Health Care Financing
Jim Hahn
Specialist in Health Care Financing
Suzanne M. Kirchhoff
Analyst in Health Care Financing
Paulette C. Morgan
Specialist in Health Care Financing
Sibyl Tilson
Specialist in Health Care Financing
January 31, 2013
Congressional Research Service
Medicare Primer
Congressional Research Service
Medicare is a federal program that pays for covered health care services of qualified
beneficiaries. It was established in 1965 under Title XVIII of the Social Security Act to provide
health insurance to individuals 65 and older, and has been expanded over the years to include
permanently disabled individuals under 65. Medicare, which consists of four parts (A-D), covers
hospitalizations, physician services, prescription drugs, skilled nursing facility care, home health
visits, and hospice care, among other services.
Generally, individuals are eligible for Medicare if they or their spouse worked for at least 40
quarters in Medicare-covered employment, are 65 years old, and are a citizen or permanent
resident of the United States. Individuals may also qualify for coverage if they are a younger
person with a permanent disability, have End-Stage Renal disease (permanent kidney failure
requiring dialysis or transplant), or have amyotrophic lateral sclerosis (ALS, Lou Gehrig’s
disease). The program is administered by the Centers for Medicare & Medicaid Services (CMS),
and by private entities that contract with CMS to provide claims processing, auditing, and quality
oversight services.
In FY2013, the program will cover approximately 52 million persons (43 million aged and 9
million disabled) at a total cost of about $606 billion, accounting for approximately 3.7% of GDP.
Spending under the program (except for a portion of administrative costs) is considered
mandatory spending and is not subject to the appropriations process. Services provided under
Parts A and B (also referred to as “traditional Medicare”), are generally paid directly by the
government on a “fee-for-service” basis, using different prospective payment systems or fee
schedules. Under Parts C and D, private insurers are paid a monthly “capitated” amount to
provide enrollees with at least a minimum standard benefit. Medicare is required to pay for all
covered services provided to eligible persons, so long as specific criteria are met.
Since 1965, the Medicare program has undergone considerable change. For example, during the
111th Congress, the Patient Protection and Affordable Care Act (ACA; P.L. 111-148 and P.L. 111-
152) made numerous changes to the Medicare program that modify provider reimbursements,
provide incentives to increase the quality and efficiency of care, and enhance certain Medicare
benefits. However, in the absence of further congressional action, the Medicare program is
expected to be unsustainable in the long run. The Hospital Insurance (Part A) trust fund has been
estimated to become insolvent in 2024. Additionally, although the Supplementary Medical
Insurance (Parts B and D) trust fund is financed in large part through federal general revenues and
cannot become insolvent, associated spending growth is expected to put increasing strains on the
country’s competing priorities. As such, Medicare is expected to be a high-priority issue in the
113th Congress, and Congress may consider a variety of Medicare reform options ranging from
further modifications of provider payment mechanisms to redesigning the entire program.
Medicare Primer
Congressional Research Service
Introduction ...................................................................................................................................... 1
Medicare History ............................................................................................................................. 2
Eligibility and Enrollment ............................................................................................................... 5
Benefits and Payments ..................................................................................................................... 7
Part A ......................................................................................................................................... 7
Inpatient Hospital Services .................................................................................................. 8
Skilled Nursing Facility (SNF) Services ............................................................................. 9
Hospice Care ....................................................................................................................... 9
Parts A and B ........................................................................................................................... 10
Home Health Services ....................................................................................................... 10
End-Stage Renal Disease (ESRD) ..................................................................................... 10
Part B ....................................................................................................................................... 11
Physicians and Non-physician Practitioner Services ........................................................ 12
Therapy Services ............................................................................................................... 13
Preventive Services ........................................................................................................... 13
Clinical Lab and other Diagnostic Tests ............................................................................ 14
Durable Medical Equipment, Prosthetics, Orthotics and Supplies (DMEPOS) ................ 14
Part B Drugs and Biologics ............................................................................................... 15
Hospital Outpatient Department Services ......................................................................... 15
Ambulatory Surgical Center Services ............................................................................... 16
Ambulance ........................................................................................................................ 17
Rural Health Clinics and Federally Qualified Health Centers .......................................... 17
Part C, Medicare Advantage .................................................................................................... 18
Part D ....................................................................................................................................... 19
Administration ............................................................................................................................... 21
Financing ....................................................................................................................................... 23
Part A Financing ...................................................................................................................... 24
Part B Financing ...................................................................................................................... 25
Part C Financing ...................................................................................................................... 26
Part D Financing ...................................................................................................................... 26
Additional Insurance Coverage ..................................................................................................... 26
Figure 1. Projected Medicare Benefit Spending, by Category, FY2013 .......................................... 2
Figure 2. 2013 Standard Medicare Prescription Drug Benefit ....................................................... 20
Figure 3. Sources of Medicare Revenue: 2011 .............................................................................. 24
Table B-1. Part A (Hospitalization Insurance) ............................................................................... 31
Medicare Primer
Congressional Research Service
Table B-2. Part B (Supplementary Medical Insurance) ................................................................. 32
Table B-3. Part C (Medicare Advantage) ....................................................................................... 32
Table B-4. Part D (Outpatient Prescription Drug Benefit) ............................................................. 33
Appendix A. Acronyms.................................................................................................................. 28
Appendix B. 2013 Medicare Beneficiary Costs ............................................................................ 31
Author Contact Information........................................................................................................... 33
Medicare Primer
Congressional Research Service 1
Medicare is a federal program that pays for covered health care services of qualified
beneficiaries. It was established in 1965 under Title XVIII of the Social Security Act to provide
health insurance to individuals 65 and older, and has been expanded over the years to include
permanently disabled individuals under 65. The program is administered by the Centers for
Medicare & Medicaid Services (CMS),1 within the U.S. Department of Health and Human
Services (HHS).
Medicare consists of four distinct parts:
• Part A (Hospital Insurance, or HI) covers inpatient hospital services, skilled
nursing care, hospice care, and some home health services. The HI trust fund is
mainly funded by a dedicated payroll tax of 2.9% of earnings, shared equally
between employers and workers.
• Part B (Supplementary Medical Insurance, or SMI) covers physician services,
outpatient services, and some home health and preventive services. The SMI trust
fund is funded through beneficiary premiums (set at 25% of estimated program
costs for the aged) and general revenues (the remaining amount, approximately
• Part C (Medicare Advantage, or MA) is a private plan option for beneficiaries
that covers all Parts A and B services, except hospice. Individuals choosing to
enroll in Part C must also enroll in Part B. Part C is funded through the HI and
SMI trust funds.
• Part D covers outpatient prescription drug benefits. Funding is included in the
SMI trust fund and is financed through beneficiary premiums, general revenues,
and state transfer payments.
Medicare serves approximately one in six Americans and virtually all of the population aged 65
and over. In 2013, the program will cover an estimated 52 million persons (43 million aged and 9
million disabled). The Congressional Budget Office (CBO) estimates that total Medicare
spending in 2013 will be about $606 billion, accounting for approximately 3.7% of GDP. In 2013,
spending on benefits will be approximately $590 billion. Almost a third of Medicare benefit
spending is for hospital inpatient and outpatient services (see Figure 1). CBO also estimates that
federal Medicare spending (after deduction of beneficiary premiums and other offsetting receipts)
will be close to $510 billion in 2013, accounting for about 13.9% of total federal spending.
Medicare is required to pay for all covered services provided to eligible persons, so long as
specific criteria are met. Spending under the program (except for a portion of administrative
costs) is considered mandatory spending and is not subject to the appropriations process.
Medicare is expected to be a high-priority issue in the 113th Congress. The program has a
significant impact on beneficiaries and other stakeholders as well as on the economy in general
through its coverage of important health care benefits for the aged and disabled, the payment of
premiums and other cost-sharing by those beneficiaries, its payments to providers who supply
those health care services, and its interaction with other insurance coverage. Projections of future
1 Appendix A provides a list of commonly used acronyms in this report, including acronyms for Public Laws.
Medicare Primer
Congressional Research Service 2
Medicare expenditures and funding indicate that the program will place increasing financial
demands on the federal budget and on beneficiaries. In response to these concerns, Congress may
consider a range of Medicare reform options, from making changes within the current structure,
including modifying provider payments and revising existing oversight and regulatory
mechanisms, to restructuring the entire program.
The Committees of jurisdiction for the mandatory spending (benefits) portion of Medicare are the
Senate Committee on Finance, the House Committee on Ways and Means, and the House
Committee on Energy and Commerce. The House and Senate Committees on Appropriations
have jurisdiction over the discretionary spending used to administer and oversee the program.
Figure 1. Projected Medicare Benefit Spending, by Category, FY2013
($590 Billion*)
$148 B
(includes other
group health
Other Services
(includes hospice,
durable medical
ambulance and
laboratory services,
Part B drugs,
outpatient dialysis)
Part A
Part A and/or B
Part B
Part C
Part D
Source: Figure by CRS based on data from the Congressional Budget Office, March 2012 Medicare Baseline.
Note: *The $590 billion for benefit payments does not include estimated reductions under sequestration,
administration costs or recoveries.
Medicare History
Medicare was enacted in 1965 (P.L. 89-97) in response to the concern that only about half of the
nation’s seniors had health insurance, and most of those had coverage only for inpatient hospital
costs. The new program, which became effective July 1, 1966, included Part A coverage for
hospital and post-hospital services and Part B coverage for doctors and other medical services. As
is the case for the Social Security program, Part A is financed by payroll taxes levied on current
workers and their employers; persons must pay into the system for 40 calendar quarters to
become entitled to premium-free benefits. Medicare Part B is voluntary, with a monthly premium
Medicare Primer
Congressional Research Service 3
required of beneficiaries who choose to enroll. Payments to health care providers under both Part
A and Part B were originally based on the most common form of payment at the time, namely
“reasonable costs” for hospital and other institutional services or “usual, customary and
reasonable charges”2 for physicians and other medical services.
Medicare is considered a social insurance program and is the second largest such federal program,
after Social Security. The 1965 law also established Medicaid, the federal/state health insurance
program for the poor; this was an expansion of previous welfare-based assistance programs.
Some low-income individuals qualify for both Medicare and Medicaid.
In the ensuing years, Medicare has undergone considerable change. P.L. 92-603, enacted in 1972,
expanded program coverage to certain individuals under 65 (the disabled and persons with endstage
renal disease (ESRD)),3 and introduced managed care into Medicare by allowing private
insurance entities to provide Medicare benefits in exchange for a monthly capitated payment.
This law also began to place limitations on the definitions of reasonable costs and charges in
order to gain some control over program spending which, even initially, exceeded original
During the 1980s and 1990s, a number of laws were enacted that included provisions designed to
further stem the rapid increase in program spending through modifications to the way payments
to providers were determined, and to postpone the insolvency of the Medicare Part A trust fund.
This was typically achieved through tightening rules governing payments to providers of services
and limiting the annual updates in such payments. The program moved from payments based on
reasonable costs and reasonable charges to payment systems under which a predetermined
payment amount was established for a specified unit of service. At the same time, beneficiaries
were given expanded options to obtain covered services through private managed care
arrangements, typically health maintenance organizations (HMOs). Most Medicare payment
provisions were incorporated into larger budget reconciliation bills designed to control overall
federal spending.
This effort culminated in the enactment of the Balanced Budget Act of 1997 (BBA 97, P.L. 105-
33).4 This law slowed the rate of growth in payments to providers and established new payment
systems for certain categories of providers. It also established the Medicare+Choice program,
which expanded private plan options for beneficiaries and changed the way most of these plans
were paid. BBA 97 further expanded preventive services covered by the program.
Subsequently, Congress became concerned that the BBA 97 cuts in payments to providers were
somewhat larger than originally anticipated. Therefore, legislation was enacted in both 1999
(Balanced Budget Refinement Act of 1999, BBRA, P.L. 106-113) and 2000 (Medicare, Medicaid,
2 Also known as “customary, prevailing and reasonable charges,” this method based physician payments on charges
commonly used by physicians in a local community. The payment for a service was the lowest of (1) the physician’s
billed charge for the service, (2) the physician’s customary charge for the service, or (3) the prevailing charge for that
service in the community.
3 ESRD is a stage of kidney impairment that appears to be irreversible and permanent, requiring a regular course of
dialysis treatments or a kidney transplantation to maintain life.
4 For additional information on major legislative changes to Medicare from 1997 through 2012, see Chapter 2 of the
House Committee on Ways and Means 2012 Greenbook at
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Congressional Research Service 4
and SCHIP Benefits Improvement and Protection Act of 2000, BIPA, P.L. 106-554) to mitigate
the impact of BBA 97 on providers.
In 2003, Congress enacted the Medicare Prescription Drug, Improvement, and Modernization Act
of 2003 (MMA, P.L. 108-173),5 which included a major benefit expansion and placed increasing
emphasis on the private sector to deliver and manage benefits. The MMA included provisions that
(1) created a new voluntary outpatient prescription drug benefit to be administered by private
entities; (2) replaced the Medicare+Choice program with the Medicare Advantage (MA) program
and raised payments to plans in order to increase their availability for beneficiaries; (3)
introduced the concept of income testing into Medicare, with higher-income persons paying
larger Part B premiums beginning in 2007;6 (4) modified some provider payment rules; (5)
expanded covered preventive services; and (6) created a specific process for overall program
review if general revenue spending exceeded a specified threshold.7
During the 109th Congress, two laws were enacted that incorporated minor modifications to
Medicare’s payment rules. These were the Deficit Reduction Act of 2005 (DRA, P.L. 109-171)
and the Tax Relief and Health Care Act of 2006 (TRHCA, P.L. 109-432). In the 110th Congress,
additional changes were incorporated in the Medicare, Medicaid, and SCHIP Extension Act of
2007 (MMSEA, P.L. 110-173)8 and the Medicare Improvements for Patients and Providers Act of
2008 (MIPPA, P.L. 110-275).9
In the 111th Congress, comprehensive health reform legislation was enacted that, among other
things, made statutory changes to the Medicare program. The Patient Protection and Affordable
Care Act (ACA; P.L. 111-148), enacted on March 23, 2010, included numerous provisions
affecting Medicare payments, payment rules, covered benefits, and the delivery of care. The
Health Care and Education Affordability Reconciliation Act of 2010 (the Reconciliation Act, or
HCERA; P.L. 111-152), enacted on March 30, 2010, made changes to a number of Medicarerelated
provisions in the ACA and added several new provisions.10 Included in the ACA, as
amended, are provisions that (1) constrain Medicare’s annual payment increases for certain
providers; (2) change payment rates in the Medicare Advantage program so that they more
closely resemble those in fee-for-service; (3) reduce payments to hospitals that serve a large
number of low-income patients; (4) create an Independent Payment Advisory Board (IPAB) that
will make recommendations to adjust Medicare payment rates;11 (5) phase out the Part D
prescription drug benefit “doughnut hole”; (6) increase resources and enhance activities to
prevent fraud and abuse; and (7) provide incentives to increase the quality and efficiency of care,
such as creating value-based purchasing programs for certain types of providers, allowing
accountable care organizations (ACOs) that meet certain quality and efficiency standards to share
5 For more information, see CRS Report RL31966, Overview of the Medicare Prescription Drug, Improvement, and
Modernization Act of 2003.
6 See CRS Report R40082, Medicare: Part B Premiums, by Patricia A. Davis.
7 See CRS Report RS22796, Medicare Trigger, by Patricia A. Davis, Christopher M. Davis, and Todd Garvey.
8 For more information, see CRS Report RL34360, P.L. 110-173: Provisions in the Medicare, Medicaid, and SCHIP
Extension Act of 2007.
9 For more information, see CRS Report RL34592, P.L. 110-275: The Medicare Improvements for Patients and
Providers Act of 2008.
10 For more information, see CRS Report R41196, Medicare Provisions in the Patient Protection and Affordable Care
Act (PPACA): Summary and Timeline, and CRS General Distribution Memorandum, Estimates of Medicare Savings in
the Patient Protection and Affordable Care Act, by Patricia A Davis, August 31, 2012, available upon request.
11 See CRS Report R41511, The Independent Payment Advisory Board, by Jim Hahn and Christopher M. Davis.
Medicare Primer
Congressional Research Service 5
in the savings,12 creating a voluntary pilot program that bundles payments for physician, hospital,
and post-acute care services, and adjusting payments to hospitals for readmissions related to
certain potentially preventable conditions.
During the first session of the 112th Congress, on August 2, 2011, the Budget Control Act of 2011
(BCA; P.L. 112-25) was enacted. It provided for increases in the debt limit and established
procedures designed to reduce the federal budget deficit, including the creation of a Joint Select
Committee on Deficit Reduction.13 The failure of the Joint Committee to propose budget
reduction legislation by its mandated deadline triggered automatic spending reductions
(“sequestration”) in years 2013 through 2021. The American Taxpayer Relief Act of 2012
(ATRA, P.L. 112-240), signed into law January 2, 2013, delayed the automatic reductions by two
months.14 Unless Congress takes action to prevent these cuts, most Medicare program
expenditures will be subject to reductions of up to 2% each year.15
Under sequestration, Medicare’s benefit structure would generally remain unchanged; however,
most Medicare plans and providers would see a reduction in their Medicare payments. Spending
for certain Medicare payments are exempt from sequestration and would therefore not be
reduced. These exemptions include (1) Part D low-income subsidies, (2) the Part D catastrophic
subsidy, and (3) Qualified Individual (QI) premiums. Some Medicare administrative and
operational expenditures could be subject to reductions higher than 2%.16 Prior to the enactment
of ATRA, CBO estimated that Medicare spending reductions would total approximately $123
billion over nine years.17
Eligibility and Enrollment
Most persons aged 65 or older are automatically entitled to premium-free Part A because they or
their spouse paid Medicare payroll taxes for at least 40 quarters (10 years) on earnings covered by
either the Social Security or the Railroad Retirement systems. Persons under age 65 who receive
cash disability benefits from Social Security or the Railroad Retirement systems for at least 24
months are also entitled to Part A. (Since there is a five-month waiting period for cash payments,
the Medicare waiting period is effectively 29 months.)18 The 24-month waiting period is waived
12 Groups of providers and suppliers who work together to manage and coordinate care for Medicare fee-for-service
beneficiaries. See CRS Report R41474, Accountable Care Organizations and the Medicare Shared Savings Program,
by Amanda K. Sarata.
13 For a comprehensive discussion of the BCA, see CRS Report R41965, The Budget Control Act of 2011, by Bill
Heniff Jr., Elizabeth Rybicki, and Shannon M. Mahan.
14 For additional information, see CRS Report R42884, The “Fiscal Cliff” and the American Taxpayer Relief Act of
2012, coordinated by Mindy R. Levit.
15 Section 256(d) of the Balanced Budget and Emergency Deficit Control Act of 1985 (BBEDCA, P.L. 99-177)
contains special rules for the Medicare program in case of a sequestration. While BBEDCA ordinarily limits reduction
of certain Medicare spending to 4% under a sequestration order, the BCA limits the size of this reduction to 2%. See
CRS Report R42050, Budget “Sequestration” and Selected Program Exemptions and Special Rules, coordinated by
Karen Spar for additional detail.
16 OMB will determine which parts of the Medicare program fall under the 2% cap and which could be subject to
higher caps.
17 Congressional Budget Office, Estimated Impact of Automatic Budget Enforcement Procedures Specified in the
Budget Control Act, September 12, 2011, .
18 For more information, see CRS Report RS22195, Social Security Disability Insurance (SSDI) and Medicare: The 24-
Month Waiting Period for SSDI Beneficiaries Under Age 65, by Scott Szymendera.
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for persons with amyotrophic lateral sclerosis (ALS, “Lou Gehrig’s disease”). Individuals of any
age with ESRD who receive dialysis on a regular basis or a kidney transplant are eligible for
Medicare. Medicare coverage for individuals with ESRD usually starts the first day of the fourth
month of dialysis treatments. In addition, individuals with one or more specified lung diseases or
types of cancer who lived for six months during a specified period prior to diagnosis in an area
subject to a public health emergency declaration by the Environmental Protection Agency (EPA)
as of June 17, 2009, are also deemed entitled to benefits under Part A and eligible to enroll in
Part B.
Persons over age 65 who are not entitled to premium-free Part A may obtain coverage by paying a
monthly premium ($441 in 2013) or, for persons with at least 30 quarters of covered employment,
a reduced monthly premium ($243 in 2013). In addition, disabled persons who lose their cash
benefits solely because of higher earnings, and subsequently lose their extended Medicare
coverage, may continue their Medicare enrollment by paying a premium, subject to limitations.
Generally, enrollment in Medicare Part B is voluntary. All persons entitled to Part A (and persons
over 65 not entitled to premium-free Part A) may enroll in Part B by paying a monthly
premium.19 For most Part B enrollees, the 2013 monthly premium is $104.90. Higher income
enrollees pay higher premiums. (See the “Part B Financing” section below.) While enrollment in
Part B is voluntary for most individuals, in most cases, those who voluntarily enroll in Part A
must also enroll in Part B. Additionally, ESRD beneficiaries and Medicare Advantage enrollees
(discussed below) must also enroll in Part B.
Together, Parts A and B of Medicare comprise “original Medicare,” which covers benefits on a
fee-for-service (FFS) basis. Beneficiaries have another option for coverage through private plans,
called the Medicare Advantage (MA or Part C) program. When beneficiaries first become eligible
for Medicare, they may choose either original Medicare or they may enroll in a private MA plan.
Each fall, there is an annual open enrollment period during which time Medicare beneficiaries
may choose a different MA plan, or leave or join the MA program.20 Beneficiaries are to receive
information about their options to help them make informed decisions.21 In 2013, the annual open
enrollment period will be from October 15 to December 7 for plan choices starting the following
January. Starting in 2012, MA plans with a 5-star quality rating are allowed to enroll Medicare
beneficiaries who are either in traditional Medicare or in an MA plan with a lower quality rating
at any time.
Finally, each individual enrolled in either Part A or Part B is also entitled to obtain qualified
prescription drug coverage through enrollment in a Part D prescription drug plan. Similar to Part
B, enrollment in Part D is voluntary and the beneficiary pays a monthly premium. Beginning in
19 See CRS Report R40082, Medicare: Part B Premiums, by Patricia A. Davis.
20 Starting in 2011, MA enrollees are only permitted to drop out of their MA plans and return to original Medicare
during the first 45-day period of each calendar year. Though they are no longer allowed to switch to another MA plan
as they were able to do previously, MA enrollees who use the 45-day period to disenroll from their MA plan may enroll
in a stand-alone Part D prescription drug plan (PDP), or may elect to enroll in other non-Medicare Advantage private
plan options, such as a Medicare Cost plan or a demonstration plan. MA enrollees will still be able to switch plans
during special enrollment periods, such as when an MA enrollee moves outside his or her plan’s service area or if an
enrollee’s MA plan is terminated.
21 In addition to the yearly Medicare & You Handbook,,
which is mailed to beneficiaries’ homes, beneficiaries can consult to find information such as
the items and services covered under Medicare, cost sharing requirements, participating medical providers and private
health plan, and nursing home quality scores.
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Congressional Research Service 7
2011, some higher-income enrollees pay higher premiums, similar to enrollees in Part B.
Generally, beneficiaries enrolled in an MA plan providing qualified prescription drug coverage
(MA-PD plan) must obtain their prescription drug coverage through that plan.22
In general, individuals who do not enroll in Part B or Part D during an initial enrollment period
(when they first become eligible for Medicare) must pay a permanent penalty of increased
monthly premiums if they choose to enroll at a later date. Individuals who do not enroll in Part B
during their initial enrollment period may enroll only during the annual open enrollment period,
which occurs from January 1–March 31 each year. Coverage begins the following July 1.
However, the law waives the Part B late enrollment penalty for current workers who have
primary coverage through their own or a spouse’s employer-sponsored plan. These individuals
have a special enrollment period once their employment ends; as long as they enroll in Part B
during this time, they will not be subject to penalty.23
Individuals who do not enroll in Part D during their initial enrollment period may enroll during
the annual open enrollment period, which corresponds with the Part C annual enrollment
period—from October 15 to December 7, with coverage effective the following January.
Individuals are not subject to the Part D penalty if they have maintained “creditable” drug
coverage through another source, such as retiree health coverage offered by a former employer or
union. However, once employees retire or have no access to “creditable” Part D coverage, a
penalty will apply unless they sign up for coverage during a special enrollment period. Finally,
for persons who qualify for the low-income subsidy for Part D, the delayed-enrollment penalty
does not apply.
Benefits and Payments
Medicare Parts A, B, and D each cover different services, with Part C providing a private plan
alternative for Medicare services, except hospice. The Parts A-D covered services are described
below, along with a description of Medicare’s payments.
Part A
Part A provides coverage for inpatient hospital services, post-hospital skilled nursing facility
(SNF) services, hospice care, and some home health services, subject to certain conditions and
limitations. Approximately 18% of Part A enrollees use Part A services during a year.
22 If a Medicare beneficiary enrolls in a Private Fee-for-Service (PFFS) plan that does not provide drug coverage, he or
she may enroll in a stand-alone Prescription Drug Plan (PDP). However, enrollees in other types of MA plans who
want Part D prescription drug coverage must choose a Medicare Advantage Prescription Drug (MA-PD) plan, which is
an MA plan that provides all Medicare required parts A, B, and D benefits. If a Medicare beneficiary enrolls in a local
HMO or regional PPO that does not offer drug coverage, he or she does not have the option to enroll in a stand-alone
PDP plan.
23 For additional information on enrollment periods see Medicare Publication “Understanding Medicare Enrollment
Periods,” at
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Inpatient Hospital Services
Medicare inpatient hospital services include (1) bed and board; (2) nursing services; (3) use of
hospital facilities; (4) drugs, biologics, supplies, appliances, and equipment; and (5) diagnostic
and therapeutic items and services. (Physicians’ services provided during an inpatient stay are
paid under the physician fee schedule and discussed below in the “Physicians and Non-physician
Practitioner Services” section.) Coverage for inpatient services is linked to an individual’s benefit
period or “spell of illness” (defined as beginning on the day a patient enters a hospital and ending
when he or she has not been in a hospital or skilled nursing facility for 60 days). An individual
admitted to a hospital more than 60 days after the last discharge from a hospital or SNF begins a
new benefit period. Coverage in each benefit period is subject to the following conditions:
• Days 1-60. Beneficiary pays a deductible ($1,184 in 2013).
• Days 61-90. Beneficiary pays a daily coinsurance charge ($296 in 2013).
• Days 91-150. After 90 days, the beneficiary may draw on one or more of 60
lifetime reserve days, provided they have not been previously used. (Each of the
60 lifetime reserve days can be used only once during an individual’s lifetime.)
For lifetime reserve days, the beneficiary pays a daily coinsurance charge ($592
in 2013); otherwise the beneficiary pays all costs.
• Days 151 and over. Beneficiary pays for all costs for these days.
Inpatient mental health care in a psychiatric facility is limited to 190 days during a patient’s
lifetime. Cost sharing is structured similarly to that for stays in a general hospital (above).
Medicare makes payments to most acute care hospitals under the inpatient prospective payment
(IPPS) system, using a prospectively determined amount for each discharge. Medicare’s
payments to hospitals is the product of two components: (1) a discharge payment amount adjusted
by a wage index for the area where the hospital is located or where it has been reclassified, and
(2) the weight associated with the Medicare severity-diagnosis related group (MS-DRG) to which
the patient is assigned. This weight reflects the relative costliness of the average patient in that
MS-DRG, which is revised annually, generally effective October 1st of each year.
Additional payments are made to hospitals for cases with extraordinary costs (outliers), indirect
costs incurred by teaching hospitals for graduate medical education, and disproportionate share
hospital (DSH) payments to those hospitals serving a certain volume of low-income patients.
Additional payments may also be made for qualified new technologies that have been approved
for special add-on payments. In FY2013, certain low volume hospitals will receive an add-on
payment for each Medicare discharge, an amount that ranges from 25% for hospitals with less
than 200 Medicare discharges to no adjustment for hospitals with more than 1,600 Medicare
discharges. Prospective payments are also made for inpatient capital costs.
Medicare also makes payments outside the IPPS system for direct costs associated with graduate
medical education (GME) for hospital residents, subject to certain limits. In addition, Medicare
reimburses hospitals for 65% of the allowable costs associated with beneficiaries’ unpaid
deductible and copayment amounts as well as for the costs for certain other services.
Additional payments or special treatment may apply for hospitals meeting one of the following
designations: (1) sole community hospitals (SCHs), (2) Medicare dependent hospitals, and (3)
rural referral centers. Certain hospitals or distinct hospital units are exempt from IPPS and paid
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on an alternative basis,24 including (1) inpatient rehabilitation facilities, (2) long-term care
hospitals, (3) psychiatric facilities including hospitals and distinct part units, (4) children’s
hospitals and cancer hospitals, and (5) critical access hospitals.
Skilled Nursing Facility (SNF) Services
Medicare covers up to 100 days of post-hospital care for persons needing skilled nursing or
rehabilitation services on a daily basis.25 The SNF stay must be preceded by an inpatient hospital
stay of at least three days, and the transfer to the SNF typically must occur within 30 days of the
hospital discharge. There is no beneficiary cost-sharing for the first 20 days of a Medicarecovered
SNF stay. For days 21 to 100 beneficiaries are subject to daily coinsurance charges ($148
in 2013). The 100-day limit begins again with a new spell of illness.
SNF services are paid under a prospective payment system (PPS), which is based on a per diem
urban or rural base payment rate, adjusted for case mix (average severity of illness) and area
wages. The per diem rate generally covers all services, including room and board, provided to the
patient that day. The case-mix adjustment is made using the resource utilization groups (RUGs)
classification system, which uses patient assessments to assign a beneficiary to one of 66 groups
that reflect the beneficiary’s expected use of services. Patient assessments are done at various
times during a patient’s stay and the RUG category a beneficiary is placed in can change with
changes in the beneficiary’s condition. Extra payments are not made for extraordinarily costly
cases (“outliers”).
Hospice Care
The Medicare hospice benefit covers services designed to provide palliative care and
management of a terminal illness; the benefit includes drugs and medical and support services.
These services are provided to Medicare beneficiaries with a life expectancy of six months or less
for two 90-day periods, followed by an unlimited number of 60-day periods. The individual’s
attending physician and the hospice physician must certify the need for the first benefit period,
but only the hospice physician needs to recertify for subsequent periods. Starting January 1, 2011,
a hospice physician or nurse practitioner must have a face-to-face encounter with the individual to
determine continued eligibility prior to the 180th day recertification, and for each subsequent
recertification. Hospice care is provided in lieu of most other Medicare services related to the
curative treatment of the terminal illness. Beneficiaries electing hospice care from a hospice
program may receive curative services for illnesses or injuries unrelated to their terminal illness
and they may disenroll from the hospice at any time. Nominal cost-sharing is required for drugs
and respite care.
Payment for hospice care is based on one of four prospectively determined rates (which
correspond to four different levels of care) for each day a beneficiary is under the care of the
hospice. The four rate categories are routine home care, continuous home care, inpatient respite
care, and general inpatient care. Payment rates are adjusted to reflect differences in area wage
24 Hospitals in the state of Maryland are exempt from the IPPS and are paid under a state-specific payment system.
25 For additional information on skilled nursing facility benefits, see CRS Report R42401, Medicare’s Skilled Nursing
Facility Primer: Benefit Basics and Issues, by Scott R. Talaga.
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levels, using the hospital wage index.26 Payments to a hospice are subject to an aggregate cap
based on a cap amount and the number of beneficiaries who received hospice services during the
cap year (November 1 to October 31). The cap amount is adjusted annually by changes to the
medical care expenditure category of the Consumer Price Index for all urban consumers (CPI-U).
Parts A and B
Home health services and services for individuals with end-stage renal disease are covered under
both Parts A and B of Medicare.
Home Health Services
Medicare covers visits by participating home health agencies for beneficiaries who (1) are
confined to home, (2) need skilled nursing care on an intermittent basis, or (3) need physical or
occupational therapy or speech language therapy. After establishing such eligibility, the
continuing need for occupational therapy services may extend the eligibility period. Covered
services include part-time or intermittent nursing care, physical or occupational therapy or speech
language pathology services, medical social services, home health aide services, and medical
supplies and durable medical equipment. The services must be provided under a plan of care
established by a physician, and the plan must be reviewed by the physician at least every 60 days.
Home health services are covered under both Medicare Parts A and B. Part A covers up to 100
visits following a stay in a hospital or SNF. Part A also covers all home health services for
persons not enrolled in Part B. All other home health services are covered under Part B. There is
no beneficiary cost-sharing for home health services (though some other Part B services provided
in connection with the visit, such as durable medical equipment, are subject to cost-sharing
Home health services are paid under a home health PPS, based on 60-day episodes of care; a
patient may have an unlimited number of episodes. Under the PPS, for episodes with five or
greater visits a nationwide base payment amount is adjusted by differences in wages (using the
hospital wage index). This amount is then adjusted for case mix using the applicable Home
Health Resource Group (HHRG) to which the beneficiary has been assigned. The HHRG
applicable to a beneficiary is determined following an assessment of the patient’s condition and
care needs using the Outcome and Assessment Information Set (OASIS); there are 153 HHRGs.
For episodes with four or fewer visits, the PPS reimburses the provider for each visit performed.
Further payment adjustments may be made for services provided in rural areas, outlier visits (for
extremely costly patients), a partial episode for beneficiaries that have an intervening event
during their episode, or an agency’s failure to submit quality data to CMS.
End-Stage Renal Disease (ESRD)
Individuals with ESRD are eligible for all services covered under Parts A and B. Kidney
transplantation services, to the extent they are inpatient hospital services, are subject to the
26 By October 1, 2013, the Secretary will be required to implement budget neutral revisions to the methodology for
determining hospice payments for routine home care and other services. These revisions could include adjustments to
the per diem payments reflecting differences in resources used during the course of an entire episode of hospice care.
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inpatient hospital PPS and are reimbursed by both Parts A and B. However, kidney acquisition
costs are paid on a reasonable cost basis under Part A. Dialysis treatments, when an individual is
admitted to a hospital, are covered under Part A.
Individuals with ESRD are eligible for all Part B Services. Part B also covers their dialysis
services, drugs, biologicals (including erythropoiesis stimulating agents used in treating anemia
as a result of ESRD), diagnostic laboratory tests, and other items and services furnished to
individuals for the treatment of ESRD.
In effect since January 1, 2011, the new ESRD prospective payment system (PPS) makes no
payment distinction as to the site where renal dialysis services are provided. With the
implementation of the ESRD PPS, Medicare dialysis payments are bundled (phased in over four
years, 2011 through 2014) using a single payment for Medicare renal dialysis services that
includes (1) items and services included in the former payment system’s base rate as of December
31, 2010; (2) erythropoiesis stimulating agents (ESAs) for the treatment of ESRD; (3) other drugs
and biologicals for which payment was made separately (before bundling); and (4) diagnostic
laboratory tests and other items and services furnished to individuals for the treatment of ESRD.
The new system is case-mix adjusted based on factors such as patient weight, body mass index,
comorbidities, length of time on dialysis, age, race, ethnicity, and other appropriate factors as
determined by the Secretary of Health and Human Services. Under the ESRD Quality Incentive
Program, dialysis facilities that fail to meet the performance standards of the ESRD-related
quality measures receive reduced payments.
Part B
Medicare Part B covers physicians’ services, outpatient hospital services, durable medical
equipment, and other medical services. Initially, over 98% of the eligible population voluntarily
enrolled in Part B, but in recent years, the percentage has fallen to about 93%.27 Over 70% of Part
B enrollees use Part B services during a year. The program generally pays 80% of the approved
amount (most commonly, a fee schedule or other predetermined amount) for covered services in
excess of the annual deductible ($147 in 2013). The beneficiary is liable for the remaining 20%.
Most providers and practitioners are subject to limits on amounts they can bill beneficiaries for
covered services. For example, physicians and some other practitioners may choose whether or
not to accept “assignment” on a claim. When a physician accepts assignment, the physician can
only bill the beneficiary the 20% coinsurance plus any unmet deductible. When a physician
agrees to accept assignment on all Medicare claims in a given year, the physician is referred to as
a “participating physician.” There are several advantages to being a participating provider,
including higher reimbursement under the Medicare fee schedule, a lower beneficiary copayment,
and automatic forwarding of Medigap claims.
Physicians who do not agree to accept assignment on all Medicare claims in a given year are
referred to as nonparticipating physicians. Nonparticipating physicians may or may not accept
assignment for a given service. If they do not, they may charge beneficiaries more than the fee
schedule amount on nonassigned claims; however, these “balance billing” charges are subject to
27 For details, see the Annual Reports of the Board of Trustees of the Federal Hospital Insurance and Federal
Supplementary Medical Insurance Trust Funds,
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certain limits. Alternatively, physicians may choose not to accept any Medicare payment and
enter into private contracts with their patients.
For some providers, such as nurse practitioners and physician assistants, assignment is
mandatory; these providers can only bill the beneficiary the 20% coinsurance and any unmet
deductible. For other Part B services, such as durable medical equipment, assignment is optional;
for these services, applicable providers may bill beneficiaries for amounts above Medicare’s
recognized payment level and may do so without limit.28
Physicians and Non-physician Practitioner Services
Medicare Part B covers medically necessary doctors’ services and medical services provided by
some non-physician practitioners. Certain limitations apply for services provided by chiropractors
and podiatrists. Beneficiary cost-sharing is typically 20% of the approved amount, although
preventive care services require no coinsurance from the beneficiary and outpatient mental health
services are currently in the fourth of a five-year phase-in that will reduce beneficiary
responsibility from 50% to 20% by 2014.29 Covered non-physician practitioner services include,
but are not limited to, those provided by physician assistants, nurse practitioners, certified
registered nurse anesthetists, and clinical social workers.
A number of Part B services are paid under the physician fee schedule. These include services of
physicians, non-physician practitioners, and therapists. Most services described below are paid
under the physician fee schedule. There are over 7,000 service codes under the fee schedule.
The fee schedule assigns relative values to each service code. These relative values reflect
physician work (based on time, skill, and intensity involved), practice expenses, and malpractice
expenses. The relative values are adjusted for geographic variations in the costs of practicing
medicine. These geographically adjusted relative values are converted into a dollar payment
amount by a national conversion factor. The conversion factor is updated each year by a formula
specified in law. The update percentage is based on the Medicare Economic Index (MEI, which
measures changes in the prices of the inputs required to provide physician services) subject to an
adjustment to match spending under the sustainable growth rate (SGR) system, which establishes
a target for total cumulative expenditures since 1996.30 If total expenditures exceed the target, the
update for a future year is reduced. Application of the SGR formula would have led to negative
updates each year since 2002. However, Congress has acted several times to avert reductions,
thereby overriding the statutory formula for the 2003-2013 period. In recent years, the update to
the conversion factor was 0% (compared to 2009 payment levels) for January through May 2010
and 2.2% for June 2010 through December 2012.31 The ATRA extends the SGR override for
28 Certain durable medical equipment suppliers in competitive bidding areas are required to accept assignment.
29 This “mental health parity” was introduced in MIPPA (P.L. 110-275). Beneficiaries are responsible for a 35%
copayment for outpatient mental health services in 2013.
30 For details, see CRS Report R40907, Medicare Physician Payment Updates and the Sustainable Growth Rate (SGR)
System, by Jim Hahn and Janemarie Mulvey.
31 The Temporary Payroll Tax Cut Continuation Act of 2011 (P.L. 112-78) included an override of the statutory SGR
update for January and February 2012, and the Middle Class Tax Relief and Job Creation Act of 2012 (MCTRJCA,
P.L. 112-96) maintained the payment freeze through the end of 2012.
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another year and maintains physician fee schedule payments at the 2012 level through December
In addition to the fee schedule reimbursements, physicians who report on selected quality
measures for services for which quality measures are established will receive bonus payments for
those services provided beginning in July 2007. The bonus payments were 1.5% during the
second half of 2007 and for 2008, 2.0% for 2009 and 2010, 1.0% for 2011, and 0.5% in 2012. The
bonus remains at 0.5% in 2013 and 2014 for those who successfully report the measures.
Subsequently, those providers who fail to successfully report the measures will be subject to a
1.5% penalty in 2015 and a 2% penalty in 2016 and future years. Additional bonus payments will
be made for 2009-2013 for Medicare professionals providing covered services who are successful
electronic prescribers and in 2011-2014 for those who meet the requirements of a Maintenance of
Certification Program (MOCP).33
Therapy Services
Medicare covers medically necessary outpatient physician and occupational therapy, and speechlanguage
pathology services. The program has limits (therapy caps) on how much it pays for
outpatient therapy services in a calendar year. These limits are updated annually. In 2013, the
annual therapy cap amounts are 1) $1,900 for outpatient physical therapy services and speech
language pathology services; and 2) $1,900 for outpatient occupational therapy services. The
limits apply to services provided in the following settings: physical therapists in private practice,
physician offices, skilled nursing facilities (when not covered under Part A), comprehensive
outpatient rehabilitation facilities (CORFs) and other rehabilitation agencies, critical access
hospitals (CAHs), and hospital outpatient departments.34
The DRA required the Secretary to implement an exceptions process to allow continued coverage
for medically necessary services after a beneficiary has reached the therapy cap, up to a certain
limit. A series of legislative acts have extended the exceptions process and increased the limits
each year since then. In 2013, Medicare will continue to pay for therapy costs above the $1,900
cap up to $3,700 for each category of therapy service for beneficiaries who qualify for the
exception. Under certain conditions, Medicare may pay for therapy costs that exceed $3,700 a
year; however, claims for such services require supporting documentation from the therapy
provider and are subject to a higher level of review by Medicare.
Preventive Services
The original Medicare statute prohibited payment for covered items and services that are “not
reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the
functioning of a malformed body member,” which effectively excluded preventive and screening
services.35 In recent years, Congress has added and expanded Medicare coverage for a number of
32 See CRS Report R42884, The “Fiscal Cliff” and the American Taxpayer Relief Act of 2012, coordinated by Mindy
R. Levit.
33 For details, see CRS Report R41196, Medicare Provisions in the Patient Protection and Affordable Care Act
(PPACA): Summary and Timeline, coordinated by Patricia A. Davis.
34 The MCTRJCA and ATRA applied the cap and threshold to therapy services furnished in hospital outpatient
departments and critical access hospitals in 2012 and 2013.
35 Social Security Act section 1862(a)(1)(A); 42 U.S.C. 1395y(a)(1)(A).
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Congressional Research Service 14
such services through legislation, including MMA, MIPPA, and ACA. Under current law, if a
preventive service is recommended for use by the U.S. Preventive Services Task Force (USPSTF,
an independent evidence-review panel)36 and Medicare covers the service, all cost-sharing must
be waived. Also, the HHS Secretary may add coverage of a USPSTF-recommended service that is
not already covered. Coverage for preventive and screening services currently includes, among
other services: (1) a “welcome to Medicare” physical exam during the first year of enrollment in
Part B and an annual visit and prevention plan thereafter; (2) flu vaccine (annual), pneumococcal
vaccine, and hepatitis B vaccine (for persons at high risk); (3) screening tests for breast, cervical,
prostate, and colorectal cancers; (4) screening for other conditions such as depression, heart
disease, glaucoma, and osteoporosis; and (5) intensive behavioral therapy for heart disease and
for obesity.37 These services are covered under the Medicare Part B fee schedule.
Clinical Lab and other Diagnostic Tests
Part B covers clinical laboratory tests. There is no coinsurance for clinical laboratory services.
Clinical lab services are paid on the basis of area-wide (local) fee schedules. There is a ceiling on
payment amounts equal to 74% of the median of all fee schedules for the test. In general, annual
increases in clinical lab fees are based on the percentage change in the CPI-U. However,
Congress has modified the update in recent years, by (1) freezing the fee schedule amounts
through 2008 and (2) reducing the update that would otherwise apply by 0.5 percentage points
each year, for 2009-2013. The annual update to the local clinical laboratory fees for CY 2013
decreases payment by 2.95%.38
Part B also covers diagnostic x-ray tests and other diagnostic tests, as well as x-ray, radium, and
radioisotope therapy. Generally, these services are paid for under the physician fee schedule.
Durable Medical Equipment, Prosthetics, Orthotics and Supplies (DMEPOS)
Medicare covers a wide variety of equipment and devices under the heading of durable medical
equipment (DME), and prosthetics, orthotics (PO) if they are medically necessary and are
prescribed by a physician. DME is defined as equipment that (1) can withstand repeated use, (2)
is used primarily to serve a medical purpose, (3) is not generally useful in the absence of an
illness or injury, and (4) is appropriate for use in the home. DME includes such items as hospital
beds, wheelchairs, blood glucose monitors, and oxygen and oxygen equipment. It also includes
related supplies, such as drugs and biologics that are necessary for the effective use of the
product. PO is defined as items that replace all or part of a body organ, such as colostomy bags
and pacemakers, as well as leg, arm, back, and neck braces and artificial legs, arms, and eyes.
Medicare also covers some items or supplies (S), such as disposable surgical dressings that do not
meet the definitions of DME or PO.
36 U.S. Preventive Services Task Force,
37 A complete list of covered services, intervals, and limitations is available at CMS, overview of Medicare prevention,
38 See CMS Medicare Learning Network Matters Number MM8132, “Calendar Year (CY) 2013 Annual Update for
Clinical Laboratory Fee Schedule and Laboratory Services Subject to Reasonable Charge Payment,” at
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Congressional Research Service 15
Except in competitive bidding areas (described below), Medicare pays for most DMEPOS based
on fee schedules. Medicare pays 80% of the lower of the supplier’s charge for the item or the fee
schedule amount. The beneficiary is responsible for the remaining 20%. In general, fee schedule
amounts are updated each year by a (1) measure of price inflation, and (2) a measure of economywide
productivity, which may result in lower fee schedule amounts from one year to the nest.
Numerous studies and investigations have shown that Medicare pays more for certain items of
DME and PO than some other health insurers and some retail outlets.39 Such overpayments may
be due partly to the fee schedule mechanism of payment. MMA required the Secretary to
establish a Competitive Acquisition Program for certain DMEPOS in specified areas. Instead of
paying for medical equipment based on a fee schedule established by law, payment for items in
competitive bidding areas is based on the supplier bids. MIPPA delayed the program and required
the first round of the program to be re-bid, in addition to other changes. The re-bid took place in
2009 and the program started in nine metropolitan areas in January 2011.40 The second round will
expand the program to 91 additional areas. Bidding for round 2 began in January 2012, with
payments based on those bids starting in July 2013.
Part B Drugs and Biologics41
Certain specified outpatient prescription drugs and biologics are covered under Medicare Part B.
(However, most outpatient prescription drugs are covered under Part D, discussed below.)
Covered Part B drugs and biologics include drugs furnished incident to physicians’ services,
immunosuppressive drugs following a Medicare-covered organ transplant, erythropoietin for
treatment of anemia for persons with ESRD, oral anti-cancer drugs (provided they have the same
active ingredients and are used for the same indications as chemotherapy drugs which would be
covered if furnished incident to physicians services), and drugs needed for the effective use of
DME. Generally, Medicare’s reimbursement for Part B covered drugs equals 106% of the drug
manufacturer’s reported average sales price (ASP). Health care providers also receive a separate
payment for administering Medicare Part B drugs. Medicare pays 80% of the amount paid to
providers, while the beneficiaries are responsible for the remaining 20%.
Hospital Outpatient Department Services
Hospitals provide two distinct types of services to outpatients: services that are diagnostic in
nature, and other services that aid the physician in the treatment of the patient. A hospital
outpatient is a person who has not been admitted by the hospital as an inpatient but is registered
on the hospital records as an outpatient. Generally, payments under the hospital outpatient
prospective payment system (OPPS) cover the operating and capital-related costs that are directly
related and integral to performing a procedure or furnishing a service on an outpatient basis.
These payments cover services such as the use of an operating suite, treatment, procedure or
recovery room; use of an observation bed as well as anesthesia; certain drugs or pharmaceuticals;
39 See General Accounting Office (GAO) report, “Medicare Payments for Oxygen,” May 15, 1997, GAO-97-120R;
HHS Office of the Inspector General report, “Medicare Home Oxygen Equipment: Cost and Servicing,” September
2006, OEI-09-04-00420.
40 For more information, see CRS Report R41211, Medicare Durable Medical Equipment: The Competitive Bidding
Program, by Paulette C. Morgan.
41 Biologics are generally derived from living organisms rather than inorganic chemical compounds.
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Congressional Research Service 16
incidental services; and other necessary or implantable supplies or services. Payments for services
such as those provided by physicians and other professionals as well as therapy and clinical
diagnostic laboratory services, among others, are separate.
Under the OPPS, the unit of payment for acute care hospitals is the individual service or
procedure as assigned to an ambulatory payment classification (APC). To the extent possible,
integral services and items (excluding physician services paid under the physician fee schedule)
are bundled within each APC. Specified new technologies are assigned to “new technology
APCs” until clinical and cost data are available to permit assignment into a “clinical APC.”
Medicare’s hospital outpatient payment is calculated by multiplying the relative weight associated
with an APC by a conversion factor. For most APCs, 60% of the conversion factor is
geographically adjusted by the wage index used for the inpatient prospective payment system.
Except for new technology APCs, each APC has a relative weight that is based on the median cost
of services in that APC. The OPPS also includes pass-through payments for new technologies
(specific drugs, biologicals, and devices) and payments for outliers.42
Ambulatory Surgical Center Services
An ambulatory surgical center (ASC) is a distinct entity that furnishes outpatient surgical
procedures to patients who do not require an overnight stay after the procedure. According to
MedPAC, most ASCs are freestanding facilities rather than part of a larger facility, such as a
hospital. Medicare covers surgical and medical services performed in an ambulatory surgical
center (ASC) that are (1) commonly performed on an inpatient basis but may be safely performed
in an ASC; (2) not of a type that are commonly performed or that may be safely performed in
physicians’ offices; (3) limited to procedures requiring a dedicated operating room or suite and
generally requiring a post-operative recovery room or short term (not overnight) convalescent
room; and (4) not otherwise excluded from Medicare coverage.
Beginning in January 2008, Medicare pays for surgery-related facility services provided in ASCs
using a payment system based on the OPPS. (Associated physician fees are paid for separately
under the physician fee schedule.) Each of the 3,300 procedures approved for payment in an ASC
is classified into an ambulatory payment classification (APC) group on the basis of clinical and
cost similarity. The ASC system uses the same payment groups (APCs) as the OPPS, and for most
procedures, the same relative weights used in the OPPS also apply. The ASC system uses a
conversion factor based on a percentage of the OPPS conversion factor. The percentage of this
average dollar figure is set to ensure budget neutrality, so that total payments under the new ASC
payment system should equal total payments under the old ASC payment system. A different
payment method is used to set ASC payment for new, office-based procedures, separately payable
drugs, and device-intensive procedures.43 This policy also applies to separately payable radiology
services. Separately payable drugs in an ASC are paid the same amount as if provided in a
hospital outpatient department. Different rules apply for device intensive procedures (where a
device that is packaged into an APC accounts for more than half of its total payments). Separate
42 Additionally, starting in 2006, rural sole community hospitals (SCHs) receive an additional 7.1% in Medicare
payments. Special payment protections apply to cancer hospitals, children’s hospitals, small rural hospitals (that are not
SCHs) with 100 or fewer beds, and SCHs.
43 New, office-based procedures are services that are performed in physician offices at least 50% of the time. Payment
is set at the lower of the ASC rate or the practice expense portion of the physician fee schedule payment rate.
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Congressional Research Service 17
payments are made for corneal tissue acquisition, brachytherapy sources, certain radiology
services, many drugs, and certain implantable devices.
Medicare Part B covers emergency and non-emergency ambulance services to or from a hospital,
critical access hospital (CAH), or a skilled nursing facility (SNF) when other modes of
transportation could endanger the Medicare beneficiary’s health. In most cases, the program
covers 80% of the allowed amount for the service, and the beneficiary is responsible for the
remaining 20%. Generally, ambulance services are covered if: (1) transportation of the
beneficiary occurs; (2) the beneficiary is taken to an appropriate location (generally, the closest
appropriate facility); (3) the ambulance service is medically necessary (other forms of
transportation are contraindicated); (4) the ambulance provider or supplier meets state licensing
requirements; and (5) the transportation is not part of a Medicare Part A covered stay.44 Medicare
covers both scheduled and nonscheduled nonemergency transports if the beneficiary is bedconfined
or meets other medical necessity criteria. Medicare may also cover emergency
ambulance transportation in an airplane or helicopter if the beneficiary’s location is not easily
reached by ground transportation or if long distance or obstacles, such as heavy traffic, would
prevent the individual from obtaining needed care.
Medicare pays for different levels of ambulance services, which reflect the staff training and
equipment required to meet the patient’s medical condition or health needs. Generally, basic life
support (BLS) is provided by emergency medical technicians (EMTs). Advanced life support
(ALS) is provided by EMTs with advanced training or by paramedics. Medicare pays for
ambulance services according to a national fee schedule. The fee schedule establishes seven
categories of ground ambulance services and two categories of air ambulance services. Some
rural ground and air ambulance services may qualify for increased payments.45 Ambulance
providers that are CAHs, or that are entities that are owned and operated by a CAH, are paid on a
reasonable cost basis if they are the only ambulance provider within a 35 mile radius.
Rural Health Clinics and Federally Qualified Health Centers
Medicare covers Part B services in rural health clinics (RHCs) and federally qualified health
centers (FQHCs) provided by (1) physicians and specified non-physician practitioners; (2)
visiting nurses for homebound patients in home health shortage areas; (3) registered dieticians or
nutritional professionals for diabetes training and medical nutrition therapy; and (4) others, as
well as otherwise covered drugs.
RHCs and FQHCs are paid based on an “all-inclusive” rate per beneficiary visit subject to a per
visit upper limit, adjusted annually for inflation.
44 Under certain circumstances, Part B will cover an non-emergency ambulance service during a Part A covered stay,
including transport of a skilled nursing facility (SNF) resident with end-stage renal disease to and from a dialysis
facility for dialysis services.
45 For additional information, see CRS Report RL30526, Medicare Payment Updates and Payment Rates, coordinated
by Paulette C. Morgan.
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Part C, Medicare Advantage
Medicare Advantage (MA) is an alternative way for Medicare beneficiaries to receive covered
benefits. Under MA, private health plans are paid a per-person amount to provide all Medicare
covered benefits (except hospice) to beneficiaries who enroll in their plan. Medicare beneficiaries
who are eligible for Part A, enrolled in Part B, and do not have ESRD are eligible to enroll in an
MA plan if one is available in their area. Some MA plans may choose their service area (local MA
plans), while others agree to serve one or more regions defined by the Secretary (regional MA
plans). As of December 2012, nearly all Medicare beneficiaries had access to an MA plan and
approximately 27% of beneficiaries were enrolled in one. Private plans may use different
techniques to influence the medical care used by enrollees. Some plans, such as health
maintenance organizations (HMOs), may require enrollees to receive care from a restricted
network of medical providers; enrollees may be required to see a primary care physician who will
coordinate their care and refer them to specialists as necessary. Other types of private plans, such
as private fee-for-service (PFFS) plans, may look more like original Medicare, with fewer
restrictions on the providers an enrollee can see and minimal coordination of care.
In general, MA plans offer additional benefits or require smaller co-payments or deductibles than
original Medicare. Sometimes beneficiaries pay for these additional benefits through a higher
monthly premium, but sometimes they are financed through plan savings. The extent of extra
benefits and reduced cost-sharing varies by plan type and geography. However, Medicare
Advantage plans are seen by some beneficiaries as an attractive alternative to more expensive
supplemental insurance policies found in the private market.
By contract with CMS, a plan agrees to provide all required services covered in return for a
capitated monthly payment adjusted for the demographics and health history of actually enrolled
beneficiaries. The same monthly payment is made regardless of how many or few services a
beneficiary actually uses. The plan is at-risk if costs, in the aggregate, exceed program payments;
conversely, the plan can retain savings if aggregate costs are less than payments. Payments to MA
plans are based on a comparison of each plan’s estimated cost of providing Medicare covered
services (a bid) relative to the maximum amount the federal government will pay for providing
those services in the plan’s service area (a benchmark). If a plan’s bid is less than the benchmark,
its payment equals its bid plus a rebate. Starting in 2012, the size of the rebate will be dependent
on plan quality and will range from 50% to 70% of the difference between the bid and the
benchmark. The rebate must be returned to enrollees in the form of either additional benefits,
reduced cost-sharing, reduced Part B or Part D premiums, or some combination of these options.
If a plan’s bid is equal to or above the benchmark, its payment will be the benchmark amount and
each enrollee in that plan will pay an additional premium, equal to the amount by which the bid
exceeds the benchmark.
The MA benchmarks are determined through statutorily specified formulas that have changed
over time. Since BBA 97, formulas have increased the benchmark amounts, in part, to encourage
plan participation in all areas of the country. As a result, however, the benchmark amounts (and
plan payments) in some areas are higher than the average cost of original FFS Medicare. The
ACA changed the way benchmarks are calculated by tying them closer to (or below) spending in
FFS Medicare, and adjusting them based on plan quality. At the time of passage, the
Congressional Budget Office expected the ACA changes to result in reduced MA enrollment and
plan subsidies for extra benefits, though the impact was expected to vary by market.
Subsequently, the Secretary announced an MA plan quality demonstration to test whether
different structures of bonus payments lead to greater quality improvements. The demonstration
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Congressional Research Service 19
increases the size of the quality-adjusted benchmarks above levels authorized in the ACA, and
expands the number of plans eligible to receive quality-adjusted benchmarks. The demonstration
may mitigate some of the reductions in enrollment and extra plan benefits that had been expected
with the passage of the ACA.
In 2006, the MA program began to offer MA regional plans. Regional MA plans must agree to
serve one or more regions designated by the Secretary. There are 26 MA regions consisting of
states or groups of states. Regional plan benchmarks include two components: (1) a statutorily
determined amount (comparable to benchmarks described above) and (2) a weighted average of
plan bids. Thus, a portion of the benchmark is competitively determined. Similar to local plans,
plans with bids below the benchmark are given a rebate, while plans with bids above the
benchmark require an additional enrollee premium.
In general, MA eligible individuals may enroll in any MA plan that serves their area. However,
some MA plans may restrict their enrollment to beneficiaries who meet additional criteria. For
example, employer-sponsored MA plans are generally only available to the retirees of the
company sponsoring the plan. In addition, Medicare Special Needs Plans (SNPs) are a type of
coordinated care MA plan that exclusively enrolls, or enrolls a disproportionate percentage of,
special needs individuals. Special needs individuals are any MA eligible individuals who are
either institutionalized as defined by the Secretary, eligible for both Medicare and Medicaid, or
have a severe or disabling chronic condition and would benefit from enrollment in a specialized
MA plan.
Part D
Medicare Part D provides coverage of outpatient prescription drugs to Medicare beneficiaries
who choose to enroll in this optional benefit.46 (As previously discussed, Part B provides limited
coverage of some outpatient prescription drugs.) In 2012, about 60% of eligible Medicare
beneficiaries enrolled in Part D. Prescription drug coverage is provided through private
prescription drug plans (PDPs), which offer only prescription drug coverage, or through Medicare
Advantage prescription drug plans (MA-PDs), which offer prescription drug coverage that is
integrated with the health care coverage they provide to Medicare beneficiaries under Part C.
Plans must meet certain minimum requirements; however, there are significant variations among
them in benefit design, including differences in premiums, drugs included on plan formularies,
and cost-sharing for particular drugs.
Qualified Part D prescription drug plans are required to offer either “standard coverage” or
alternative coverage that has actuarially equivalent benefits. In 2013, “standard coverage” has a
$325 deductible and a 25% coinsurance for costs between $325 and $2,970. From this point, there
is minimal coverage until the beneficiary has out-of-pocket costs of $4,750 (about $6,733.75 in
total spending); this coverage gap has been labeled the “doughnut hole.” 47 Once the beneficiary
reaches the catastrophic limit, the program pays all costs except for nominal cost-sharing. In
2010, Medicare sent a tax free, one-time $250 rebate check to each Part D enrollee who reached
46 The Part D program was created by the Medicare Prescription Drug, Improvement, and Modernization Act of 2003
(P.L. 108-173), and began in 2006.
47 The actual level of total covered Part D spending before reaching the catastrophic threshold will depend on whether
the individual qualifies for the low-income subsidy and the portion of brand name and generic drugs purchased during
the coverage gap.
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the doughnut hole. Starting in 2011, the coverage gap is being gradually reduced each year until it
is eliminated in 2020.48 In 2013, a 50% discount is provided by drug manufacturers and Medicare
pays an additional 2.5% of the cost of brand-name drugs dispensed during the coverage gap. In
2013, Medicare also pays 21% of the cost of generic drugs dispensed during the coverage gap.
(See Figure 2.) By 2020, through a combination of manufacturer discounts and increased
Medicare coverage, Part D enrollees will be responsible for 25% of the costs in the coverage gap
(the same as during the initial coverage period). Most plans offer actuarially equivalent benefits
rather than the standard package, including alternatives such as reducing or eliminating the
deductible, or using tiered cost-sharing with lower cost-sharing for generic drugs.
Figure 2. 2013 Standard Medicare Prescription Drug Benefit
$325 Deductible
$2,970 in
Total Drug Costs
($986.25 out of
Coverage Gap
Plan Pays 75%
Plan Pays 15%;
Medicare Pays 80%
Enrollee Pays
Enrollee Pays
$6,733.75 in
Total Drug Costs
($4,750 out of pocket)
Initial Coverage
Enrollee Pays
47.5% Brand Drug Costs
79% Generic Drug Costs
Brand Name Drugs
50% Manufacturer
2.5% Medicare Subsidy
Source: Figure by CRS based on data from CMS, Announcement of CY 2013 Medicare Advantage Capitation
Rates and Medicare Advantage and Part D Payment Policies and Final Call Letter, Attachments IV and V.
Medicare’s payments to plans are determined through a competitive bidding process, and enrollee
premiums are tied to plan bids. Plans are paid a risk-adjusted monthly per capita amount based on
their bids during a given plan year. Part D plan sponsors determine payments for drugs and are
expected to negotiate prices. The federal government is prohibited from interfering in the price
negotiations between drug manufacturers, pharmacies, and plans (the so-called “non-interference
Part D also provides enhanced coverage for low-income enrolled individuals, such as persons
who previously received drug benefits under Medicaid (known as “dual eligibles”—enrollees in
both Medicare and Medicaid). Additionally, certain persons who do not qualify for Medicaid, but
48 For additional information, see CRS Report R41196, Medicare Provisions in the Patient Protection and Affordable
Care Act (PPACA): Summary and Timeline, coordinated by Patricia A. Davis.
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Congressional Research Service 21
whose incomes are below 150% of poverty, may also receive assistance for some portion of their
premium and cost-sharing charges.
MMA included significant incentives for employers to continue to offer coverage to their retirees
by providing a 28% federal subsidy. In 2013, the maximum potential subsidy per covered retiree
is $1,757 for employers or unions offering drug coverage that is at least actuarially equivalent
(called “creditable” coverage), to standard coverage.49 Employers or unions may select an
alternative option (instead of taking the subsidy) with respect to Part D, such as electing to pay a
portion of the Part D premiums. They may also elect to provide enhanced coverage, though this
has some financial consequences for the employer or union. Alternatively, employers or unions
may contract with a PDP or MA-PD to offer the coverage or become a Part D plan sponsor
themselves for their retirees.
CMS, a Department of Health and Human Services (HHS) operating division, administers the
Medicare program.50 CMS administers Medicare through contracts with private entities, such as
Medicare Administrative Contractors (MACs). MACs help CMS run Medicare’s day-to-day
operations by paying reimbursement claims, processing provider and supplier enrollment
applications, providing education and outreach, administering appeals, operating toll-free call
centers, and other activities.
MMA required the Secretary to implement FFS contracting reform by 2011. CMS completed
Round I of Parts A and B FFS contractor reform by awarding contracts to 15 A/B MACs to
process Parts A and B claims and four DME MACs to process DME supplier claims. CMS plans
to consolidate A/B MACs further to 10 contracts during a second round of contract awards, which
began in July 2010 when CMS issued a request for information from interested bidders.51 In
2012, CMS requested proposals from contractors for the second round of Medicare administrative
contracts. CMS awarded new contracts in September 2012; however, unsuccessful bidders
challenged CMS’s contract award decisions.52 GAO reviews contract challenges to determine if
CMS followed appropriate contracting rules and procedures. Contract challenges can take a
number of months to resolve; in the meantime, incumbent MACs continue to service the existing
geographic areas.
49 The ACA changed how these subsidies are treated for tax purposes. Originally, MMA allowed employers to exclude
the retiree drug subsidies from their gross income, as well as claim a business deduction for retiree prescription drug
expenses. Beginning in 2013, the allowed deduction for retiree prescription drug coverage is reduced by the amount of
the federal drug subsidy received. For additional information, see CRS Report R41128, Health-Related Revenue
Provisions in the Patient Protection and Affordable Care Act (ACA), by Janemarie Mulvey.
50 The Department of Health and Human Services organization chart is available at
CMS’s organization chart is at
51 For more information, see
52 For more information on the current status of CMS’s round 2 MAC rebids, see
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In addition to MACs, CMS utilizes other private entities to assist with Medicare program
operation activities.53 CMS contracts with the following private organizations to protect the
Medicare trust funds from making improper payments and to identify, recover, and where
appropriate, prosecute, waste, fraud, and abuses: Recovery Audit Contractors (RACs), Zone
Program Integrity Contractors (ZPICs), Medicare Drug Integrity Contractors (MEDICs), and
Comprehensive Error Rate Testing (CERT) contractors.54
Under MMA Sec. 306, Congress authorized a three-year demonstration to test RACs in FFS
Medicare Parts A and B, but based on early success, the demonstration was converted to a
permanent program by the Sec. 302 of the Tax Relief and Healthcare Act of 2006 (TRHCA, P.L.
109-432). ACA further expanded RACs nationwide and applied them to all Medicare Parts (C and
D, as well as A and B). Contracts were awarded to four private companies with territories that
cover approximately one-quarter of the country.55 RACs are responsible for reducing Medicare’s
improper payment rates by identifying underpayments and overpayments made to providers,
recovering overpayments, and working with providers to prevent future improper payments.
RACs are paid a contingency fee based on a percentage of the overpayments they recover from
Medicare providers and suppliers. In FY2012, the Medicare RAC contractors identified
approximately $2.4 billion in claims corrections, $2.3 billion of which were overpayments and
$109 million were underpayments.56
In addition to Medicare program integrity enhancements in MMA and ACA, Section 4241 of the
Small Business and Jobs Act of 2010 (SBJA, P.L. 111-240) appropriated $100 million for CMS to
initiate predictive modeling and other analytics technologies (“predictive analytics
technologies”).57 Predictive analytics technologies have been compared to technologies used in
private sector financial services industries, such as banking, insurance, and credit cards, to reduce
fraudulent billing. By combining data and information from multiple sources, including Medicare
FFS claims history (aberrant billing patterns), enrollment information, background checks, other
public and private information (links to questionable affiliations), and complaints, predictive
analytics technologies could help to determine if claims were legitimate before they were paid.
CMS awarded predictive modeling contracts in June 2011 to two private sector companies. In a
report on the first year of the predictive modeling program, which CMS refers to as the Fraud
Prevention System (FPS), CMS reported that approximately $115 million in potential FFS
overpayments were prevented and there was a $3 to $1 return-on-investment over the first year.58
53 Most program integrity authority was originally provided in the Health Insurance Portability and Accountability Act
of 1996 (HIPAA, P.L. 104-191), although a number of other laws have added fraud and abuse authority and sustained
HIPAA’s funding.
54 For more information on Medicare contractors and Medicare fraud and abuse, see CRS Report RL34217, Medicare
Program Integrity: Activities to Protect Medicare from Payment Errors, Fraud, and Abuse, by Cliff Binder.
55 The four FFS RACs are Region A: Diversified Collections Services, Region B: CGI, Inc., Region C: Connolly, Inc.,
and Region D: HealthDataInsights.
56 The Centers for Medicare & Medicaid Services, FY2011 Fee-for-Service Recovery Audit Program, November 2012,
57 Section 4241, “Use of Predictive Modeling and other Analytic Technologies to Identify and Prevent Waste, Fraud,
and Abuse in the Medicare Fee-for-Service Program,” of the Small Business and Jobs Act of 2010 (P.L. 111-240)
authorized a one-time $100 million appropriation from the Medicare Trust Funds. The predictive modeling funding is
available until expended. If certain interim objectives are not met by the predictive modeling program, the Secretary
may impose moratoriums on further expansion, until refinements or improvements are made.
58 Ibid.
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Medicare’s quality assurance activities are handled by state Survey Agencies and Quality
Improvement Organizations (QIOs), which operate in all states, the District of Columbia, Puerto
Rico, and the U.S. Virgin Islands. State survey agencies are responsible for inspecting Medicare
provider facilities (i.e., nursing homes, home health agencies, and hospitals) to ensure they are in
compliance with federal safety and quality standards referred to as Conditions of Participation.
QIOs monitor the quality of care delivered to Medicare beneficiaries and educate providers on the
latest quality improvement techniques.
In January 2011, CMS established a Center for Medicare and Medicaid Innovation (CMI).59 The
purpose of CMMI is to test and evaluate innovative payment and service delivery models to
reduce program expenditures under Medicare, Medicaid, and the State Children’s Health
Insurance Program (CHIP) while preserving or enhancing the quality of care furnished under
these programs. In selecting the models, the Secretary is required to give preference to those that
improve the coordination, quality, and efficiency of health care services.
Medicare’s financial operations are accounted for through two trust funds maintained by the
Department of the Treasury—the Hospital Insurance (HI) trust fund for Part A and the
Supplementary Medical Insurance (SMI) trust fund for Parts B and D. For beneficiaries enrolled
in Medicare Advantage (Part C), payments are made on their behalf in appropriate portions from
the HI and SMI trust funds. HI is primarily funded by payroll taxes, while SMI is primarily
funded through general revenue transfers and premiums. The HI and SMI trust funds are overseen
by a Board of Trustees that provides annual reports to Congress.60
The trust funds are simply accounting mechanisms; there is no actual transfer of money into and
out of a fund. Income to the trust funds is credited to the fund in the form of interest-bearing
government securities. Expenditures for services and administrative costs are recorded against the
fund. The securities represent obligations that the government has issued to itself. As long as a
trust fund has a balance, the Treasury Department is authorized to make payments for it from the
U.S. Treasury.
59 For more information, see
60 For more information on Medicare financing, see CRS Report R41436, Medicare Financing, by Patricia A. Davis.
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Figure 3. Sources of Medicare Revenue: 2011
13% 25% 11%
73% 78%
4% 3%
Payroll Taxes
General Revenue
Payments from
Taxation of Social
Security Benefits
Interest and Other
HI -
$229 Billion
$67 Billion
$234 Billion
$530 Billion
Source: 2012 Report of the Medicare Trustees, Table II.B1.
Notes: Totals may not add to 100% due to rounding.
Medicare is primarily mandatory spending—generally Medicare pays for all covered health care
services provided to beneficiaries. Aside from certain constraints in HI described below, the
program is not subject to spending limits. Additionally, most Medicare expenditures (aside from
premiums paid by beneficiaries) are paid for by current workers through ordinary income taxes
and dedicated Medicare payroll taxes, i.e., current income is used to pay current expenditures.
Medicare taxes paid by current workers are not set aside to cover their future Medicare expenses.
Part A Financing
The primary source of funding for Part A is payroll taxes paid by employees and employers. Each
pays a tax of 1.45% on the employee’s earnings; the self-employed pay 2.9%. Beginning in 2013,
some higher-income employees pay higher payroll taxes.61 Unlike Social Security, there is no
upper limit on earnings subject to the tax. Other sources of income include (1) interest on federal
securities held by the trust fund, (2) a portion of federal income taxes that individuals pay on their
social security benefits, (3) premiums paid by voluntary enrollees who are not automatically
entitled to Medicare Part A, (4) transfers from states, and (5) other revenues. Income for Part A is
credited to the HI trust fund. Part A expenditures for CY2013 are estimated to reach
61 For additional information, see Internal Revenue Service, Questions and Answers for the Additional Medicare Tax, at
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Congressional Research Service 25
approximately $280 billion.62 About $224 billion of this amount is expected to be funded by
payroll taxes and $38 billion by interest income and other sources; approximately $18 billion will
need to be drawn out of accumulated assets in the HI trust fund to make up the difference
between expected income and expenditures.
As long as the HI trust fund has a balance, the Treasury Department is authorized to make
payments for Medicare Part A services. To date, the HI trust fund has never run out of money
(i.e., become insolvent), and there are no provisions in the Social Security Act that govern what
would happen if that were to occur. Since 2008, Part A expenditures have exceeded HI income
each year, and the assets credited to the trust fund have been drawn down to make up the deficit.
The 2012 report of the Medicare Board of Trustees estimates that under current law the HI trust
fund will become insolvent in 2024 (i.e., the balance of the trust fund will reach $0), at which
time there will no longer be sufficient funds to fully cover Part A expenditures.63
Part B Financing
Medicare Part B is financed mostly from federal general revenues, with beneficiary premiums set
at 25% of estimated program costs for the aged. (The disabled pay the same premium as the
aged.) Income for Part B is credited to the SMI trust fund. Total spending for Part B is estimated
to reach about $239 billion in CY2013, with general revenues financing approximately $194
billion of that amount.64
The 2013 monthly premium is $104.90 for most Medicare beneficiaries who voluntarily enroll in
Part B. Individuals receiving Social Security benefits have their Part B premium payments
automatically deducted from their Social Security benefit checks. An individual’s Social Security
check cannot go down from one year to the next as a result of the annual Part B premium increase
(except in the case of higher-income individuals subject to income-related premiums).65
Since 2007, higher-income enrollees pay higher premiums.66 In 2013, individuals whose modified
adjusted gross income (AGI) exceeds $85,000 and each member of a couple filing jointly whose
modified AGI exceeds $170,000 are subject to higher premium amounts. These higher-income
premiums range from 35% to 80% of the value of Part B, affecting about 4% of Medicare Part B
enrollees in 2012.67 As a result of ACA, the income thresholds have been frozen at the 2010 level
62 2012 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and Federal Supplementary Medical
Insurance Trust Funds, Table III.B4, p. 60, Note, the Medicare trustees
generally report expenditures on a calendar year basis, while CBO reports on a fiscal year basis.
63 For additional information on HI solvency estimates, see CRS Report RS20946, Medicare: History of Insolvency
Projections, by Patricia A. Davis.
64 2012 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and Federal Supplementary Medical
Insurance Trust Funds, Table III.C4, p. 98,
65 See CRS Report R40082, Medicare: Part B Premiums, by Patricia A. Davis, and CRS Report R40561, Interactions
Between the Social Security COLA and Medicare Part B Premiums, by Jim Hahn.
66 For additional information, see Social Security publication, Medicare Premiums: Rules for Higher-Income
67 The higher monthly premium amounts for 2013 are based on 2011 income levels and are (1) $146.90—for single
beneficiaries with income $85,001-$107,000 or for each member of a couple filing jointly with income $170,001-
$214,000; (2) $209.80—for single beneficiaries with income $107,001-$160,000 or for each member of a couple filing
jointly with income $214,001-$320,000; (3) $272.70—for single beneficiaries with incomes $160,001-$214,000 and
each member of a couple filing jointly with income $320,001-$428,000; and (4) $335.70—for single beneficiaries with
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through 2019, which means that more people may be subject to the high-income premium over
Part C Financing
Payments for spending under the Medicare Advantage program are made in appropriate portions
from the HI and SMI trust funds. There is no separate trust fund for Part C.
Part D Financing
Medicare Part D is financed through a combination of beneficiary premiums and federal general
revenues. In addition, certain transfers are made from the states. These transfers, referred to as
“clawback payments,” represent a portion of the amounts states could otherwise have been
expected to pay for drugs under Medicaid if drug coverage for the dual eligible population had
not been transferred to Part D. Part D revenues are credited to a separate Part D account within
the SMI trust fund. In CY2013, total spending for Part D is estimated to reach approximately $79
billion, with about $60 billion of that amount paid for by general revenues.68
In 2013, the base beneficiary premium is $31.17;69 however, beneficiaries pay different premiums
depending on the plan they have selected and whether they are entitled to low-income premium
subsidies. Additionally, beginning in 2011, higher income Part D enrollees pay higher
premiums.70 (The income thresholds are the same as for Part B, as described above.) On average,
beneficiary premiums are set at 25.5% of expected total Part D costs for basic coverage.
Additional Insurance Coverage
While Medicare provides broad protection against the costs of many, primarily acute care,
services, the program does not cover all services that may be used by its aged and disabled
beneficiaries. For example, Medicare does not cover eyeglasses, hearing aids, dentures, or most
long-term care services. Further, unlike most private insurance policies, it does not include an
annual “catastrophic” cap on out-of-pocket spending on cost-sharing charges for services covered
under Parts A and B (except for persons enrolled in Medicare Advantage plans).
Most Medicare beneficiaries have some coverage in addition to Medicare. The following are the
main sources of additional coverage for Medicare enrollees.
incomes greater than $214,000 and each member of a couple filing jointly income above $428,000.
68 2012 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and Federal Supplementary Medical
Insurance Trust Funds, Table III.D3, p. 122,
69 There is no “hold harmless” provision under Part D similar to that under Part B. Part D premium increases are not
affected by Social Security cost-of-living adjustments.
70 For additional information, see Social Security publication, Medicare Premiums: Rules for Higher-Income
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• Medicare Advantage. Many MA plans offer services in addition to those covered
under original Medicare, reduced cost sharing, or reduced Part B or D premiums.
All MA plans have a catastrophic cap.71
• Employer Coverage. Coverage may be provided through a current or former
employer. In recent years, a number of employers have cut back on the scope of
retiree coverage. Some have dropped such coverage entirely, particularly for
future retirees. As noted earlier, the MMA attempted to stem this trend, at least
for prescription drug coverage, by offering subsidies to employers who offer drug
coverage, at least as good as that available under Part D.
• Medigap.72 Individual insurance policies that supplement fee-for-service
Medicare are referred to as Medigap policies. Beneficiaries with Medigap
insurance typically have coverage for a portion of Medicare’s deductibles and
coinsurance; they may also have coverage for some items and services not
covered by Medicare. Individuals select from a set of standardized plans, though
not all plans are offered in all states.
• Medicaid. Certain low-income Medicare beneficiaries also may be eligible for
full or partial benefits under their state’s Medicaid program.73 Individuals eligible
for both Medicare and Medicaid are referred to as dual eligibles. The lowestincome
dual eligibles qualify for full Medicaid benefits, so that the majority of
their health care expenses are paid by either Medicare or Medicaid; Medicare
pays first, with Medicaid picking up most of the remaining costs. In addition to
full-benefit dual eligibles, state Medicaid programs pay Medicare premiums and
some cost-sharing for other partial dual eligibles, who have higher income than
full-benefit dual eligibles but are still considered to have low income. 74
• Other Public Sources. Individuals may have additional coverage through the
Department of Veterans Affairs, or TRICARE for military retirees eligible for
Medicare (and enrolled in Part B).
In 2009, about 93% of Medicare beneficiaries had some form of additional coverage. (Some
persons may have had more than one type of additional coverage.)
71 Starting in 2011, all MA plans are required to include a maximum out-of-pocket (OOP) limit determined by CMS.
Prior to 2011, only MA regional plans were required to include a catastrophic cap on OOP spending.
72 See CRS Report R42745, Medigap: A Primer, by Carol Rapaport.
73 See CRS Report RL33202, Medicaid: A Primer, by Elicia J. Herz for additional information.
74 In addition to individuals eligible for full Medicaid benefits, other low-income Medicare beneficiaries are entitled to
limited benefits under the Medicare Savings Program (MSP). MSP includes three benefit categories each with different
benefit levels: (1) Qualified Medicare Beneficiaries (QMBs), (2) Specified Low-Income Beneficiaries (SLMB), and (3)
Qualified Individuals (QIs). For QMBs, state Medicaid programs pay Medicare Part B premiums and Medicare costsharing
(deductibles and co-payments) when beneficiaries’ incomes are under 100% of the federal poverty level (FPL).
For SLMBs, state Medicaid programs pay Part B premiums when beneficiaries’ incomes are between 100% and 120%
of the FPL. For QIs, Medicaid pays premiums when beneficiaries’ incomes are between 120% and 135% of poverty.
To be eligible for MSP, Medicare beneficiaries must also meet Medicaid’s other eligibility requirements (e.g., meet
citizenship or legal residency requirements).
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Appendix A. Acronyms
ACA Patient Protection and Affordable Care Act, as modified by the Health Care and
Education Reconciliation Act of 2010 (P.L. 111-148 and P.L. 111-152)
ACO Accountable Care Organization
AGI Adjusted Gross Income
APC Ambulatory Payment Classification
ASC Ambulatory Surgical Center
ASP Average Sales Price
ATRA American Taxpayer Relief Act of 2012 (P.L. 112-240)
BBA 97 Balanced Budget Act of 1997 (P.L. 105-33)
BBRA Medicare, Medicaid, and SCHIP Balanced Budget Refinement Act of 1999 (P.L. 106-
BCA Budget Control Act of 2011 (P.L. 112-25)
BIPA Medicare, Medicaid and SCHIP Benefits Improvement and Protection Act of 2000
(P.L. 106-554)
CAH Critical Access Hospital
CBO Congressional Budget Office
CMI Center for Medicare and Medicaid Innovation
CMS Centers for Medicare & Medicaid Services
CORF Comprehensive Outpatient Rehabilitation Facility
CPI Consumer Price Index
CPI-U Consumer Price Index for Urban Consumers
DGME Direct Graduate Medical Education
DME Durable Medical Equipment
DMEPOS Durable Medical Equipment, Prosthetics, Orthotics, and Other Medical Supplies
DRA Deficit Reduction Act of 2005 (P.L. 109-171)
DRG Diagnosis Related Group
DSH Disproportionate Share Hospital
ESRD End-Stage Renal Disease
FFS Fee-for-Service
FPL Federal Poverty Level
FQHC Federally Qualified Health Center
GAO Government Accountability Office
GDP Gross Domestic Product
GME Graduate Medical Education
HCERA Health Care and Education Reconciliation Act of 2010 (P.L. 111-152)
HHA Home Health Agency
HHRG Home Health Resource Group
HHS Department of Health and Human Services
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HI Hospital Insurance (Medicare Part A)
HMO Health Maintenance Organization
HOPD Hospital Outpatient Department
IME Indirect Medical Education
IPAB Independent Payment Advisory Board
IPF Inpatient Psychiatric Facility
IPPS Inpatient Prospective Payment System
IRF Inpatient Rehabilitation Facility
LIS Low-Income Subsidy
LTC Long-Term Care
LTCH Long-Term Care Hospital
MA Medicare Advantage
MA-PD Medicare Advantage – Prescription Drug (Plan)
MAC Medicare Administrative Contractor
MCTRJCA Middle Class Tax Relief and Job Creation Act of 2012
MedPAC Medicare Payment Advisory Commission
MEI Medical Economic Index
MIPPA Medicare Improvements for Patients and Providers Act of 2008 (P.L. 110-275)
MMA Medicare Prescription Drug Improvement and Modernization Act of 2003 (P.L.
MMSEA Medicare, Medicaid and SCHIP Extension Act of 2007 (P.L. 110-173)
MS-DRG Medicare Severity Diagnosis Related Groups
MSP Medicare Savings Program
OIG Office of Inspector General
OMB Office of Management and Budget
OPPS Outpatient Prospective Payment System
PDP Prescription Drug Plan
PFFS Private Fee-for-Service
PO Prosthetics and Orthotics
PPS Prospective Payment System
QI Qualified Individual
QIO Quality Improvement Organization
QMB Qualified Medicare Beneficiary
RAC Recovery Audit Contractor
RBRVS Resource-Based Relative Value Scale
RHC Rural Health Clinic
RUG Resource Utilization Group
SCH Sole Community Hospital
SGR Sustainable Growth Rate
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SLMB Specified Low-Income Beneficiaries
SMI Supplementary Medical Insurance (Medicare Parts B and D)
SNF Skilled Nursing Facility
SNP Special Needs Plan
SSA Social Security Act
SSI Supplemental Security Income
TRHCA Tax Relief and Health Care Act of 2006 (P.L. 109-432)
USPSTF United States Preventative Services Task Force
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Appendix B. 2013 Medicare Beneficiary Costs
Table B-1. Part A (Hospitalization Insurance)
2013 Premiums, Deductible and Additional Cost-Sharing
Individuals with: 2013 Monthly Premium
40 or more quarters of Social Security credits $0
30 - 39 quarters of Social Security credits $243
0 - 29 quarters of Social Security credits $441
Deductible and Additional Cost-Sharing
Inpatient Hospital
Deductible $1,184 per benefit period
Days 1-60 No coinsurance
Days 61-90 $296 per day
Days 91-150 $592 per day (for up to 60 lifetime reserve days)
After 150 Days Beneficiary pays 100%
Skilled Nursing Facility (SNF)
Days 1-20 No coinsurance
Days 21-100 $148 per day
After 100 Days Beneficiary pays 100%
Home Health No coinsurance
Hospice No coinsurance for hospice care; copayment of up to $5
per outpatient drug prescription
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Table B-2. Part B (Supplementary Medical Insurance)
2013 Premiums, Deductible and Additional Cost-Sharing
Yearly income in 2011 (2012 Tax Return)
File Individual Tax Return File Joint Tax Return 2013 Monthly Premiuma
$85,000 or less $170,000 or less $104.90
above $85,000 up to $107,000 above $170,000 up to $214,000 $146.90
above $107,000 up to $160,000 above $214,000 up to $320,000 $209.80
above $160,000 up to $214,000 above $320,000 up to $428,000 $272.70
above $214,000 above $428,000 $335.70
Deductible $147 per year
Additional Cost-Sharing
Physician and Non-Physician Practitioner Services 20% co-insurance, plus up to an additional 15% of the
amount if the medical provider does not accept
Outpatient Hospital Care 20% coinsurance
Ambulatory Surgical Services 20% coinsurance
Durable Medical Equipment 20% coinsurance
Physical, Occupational, and Speech Therapy 20% coinsurance, certain limits may apply
Clinical Laboratory Services No coinsurance, deductible does not apply
Home Health No coinsurance, deductible does not apply
Outpatient Mental Health Services 35% coinsurance (phasing down to 20% in 2014)
Certain Preventive Services No coinsurance
a. May be higher if enrolled late in Part B.
Table B-3. Part C (Medicare Advantage)
Premiums, deductibles and additional cost-sharing vary by plan. (See for plan
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Table B-4. Part D (Outpatient Prescription Drug Benefit)
2013 Premiums, Deductible and Additional Cost-Sharing
Premiums vary by plan. (See for plan premiums.) Higher income beneficiaries pay an
income-related monthly adjustment amount in addition to their plan premiums. Beneficiaries who receive the lowincome
subsidy generally pay no premium.
Yearly income in 2011 (2012 Tax Return)
File Individual Tax Return File Joint Tax Return 2013 Monthly Premiuma
$85,000 or less $170,000 or less Plan Premium
above $85,000 up to $107,000 above $170,000 up to $214,000 Plan Premium + $11.60
above $107,000 up to $160,000 above $214,000 up to $320,000 Plan Premium + $29.90
above $160,000 up to $214,000 above $320,000 up to $428,000 Plan Premium + $48.30
above $214,000 above $428,000 Plan Premium + $66.60
Deductible and Additional Cost-Sharing
The amounts below apply to the standard Part D benefit; actual benefits and cost-sharing requirements may vary by
plan. Beneficiaries receiving low-income subsidies pay reduced cost-sharing amounts.
Deductible $325
Initial Coverage (up to $2,970 in total drug costs) 25% coinsurance
Coverage Gap (between $2,970 and approximately
$6,733.75 in total drug costs)
Beneficiary pays 79% of the cost of generic drugs; and
47.5% of brand name drugs.
Catastrophic Coverage (above $4,750 in beneficiary out-ofpocket
Minimum of $2.65 for generic drugs, $6.60 for brand
drugs; or 5% coinsurance.
a. May be higher if enrolled late in Part D.

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