National and Local Coverage Determinations

National Coverage Determinations (NCDs) are binding on all Medicare contractors, quality improvement organizations, health maintenance organizations, competitive medical plans and health care prepayment plans. The Secretary of the Department of Health and Human Services determines whether a particular item or service is covered nationally by Medicare, which essentially grants, limits or excludes national coverage to all Medicare beneficiaries.

However, 90 percent of Medicare policies are established at the local level, providing carriers with tremendous authority over payment policy in a given state. Representatives of the ACR Radiology, Radiation Oncology, and Nuclear Medicine Carrier Advisory Committee (CAC) Network advocate on behalf of radiology for fair reimbursement policies at the local Medicare level.

By reviewing and commenting on Local Coverage Decisions (LCDs) and proposed policy changes, the CAC networks help ensure that members are appropriately reimbursed for medically reasonable and necessary services provided to Medicare patients.

National Coverage Determinations


CMS guidance documents  contain detailed information on the NCD process and decision-making factors to assist parties or organizations that may request an NCD.

Requesting an NCD 
Anyone can request an NCD from CMS. However, "aggrieved" beneficiaries, defined as "individuals entitled to benefits under Part A, or enrolled under Part B, or both, who are in need of the items or services that are the subject of the coverage determination", are given priority. CMS has outlined a specific process for requesting an NCD , which takes 9 months or more from the date the complete request is received by CMS to the date that coverage changes are implemented.

Look up an NCD » 

MEDCAC — the 
Medicare Evidence Development & Coverage Advisory Committee  — advises CMS on whether specific medical items and services are reasonable and necessary under Medicare law related to certain NCD submissions. MEDCAC performs a detailed analysis and provides comments regarding specific clinical and scientific issues in an open and public forum but CMS makes the final decision on coverage issues. 

See the current MEDCAC roster » 

Local Coverage Determinations

CAC Advisory Committee Process

What is an LCD?

Local coverage determinations (LCDS) are defined in Section 1869(f)(2)(B) of the Social Security Act (the Act). This section states: “For purposes of this section, the term ‘local coverage determination' means a determination by a fiscal intermediary or a carrier under part A or part B, as applicable, respecting whether or not a particular item or service is covered on an intermediary- or carrier-wide basis under such parts, in accordance with section 1862(a)(1)(A).” Medicare Administrative Contractors (MACs) establish LCDs.

A Medicare Administrative Contractor (MAC) is a private health care insurer that has been awarded a geographic jurisdiction to process Medicare Part A and Part B (A/B) medical claims or Durable Medical Equipment (DME) claims for Medicare Fee-For-Service (FFS) beneficiaries. CMS relies on a network of MACs to serve as the primary operational contact between the Medicare FFS program and the health care providers enrolled in the program. MACs are multi-state, regional contractors responsible for administering both Medicare Part A and Medicare Part B claims. A/B MACs process Medicare Part A and Medicare Part B claims for a defined geographic area or “jurisdiction,” servicing institutional providers, physicians, practitioners, and suppliers.

Local Medicare policies under development in your state

When a Medicare contractor develops a new LCD or significantly revises an existing one, a 45-day public comment period is required. During this time, Contractor Medical Directors (CMDs) solicit input from members of the CAC. Comments can be submitted to the CMD or electronically through your Medicare contractor's website. After the CMDs have considered all comments received, there is a 45-day notice period prior to implementation of the final LCD. Providers and billing staff should track LCD changes using the Medicare Coverage Database. The Centers for Medicare and Medicaid Services (CMS) has revised rules for the development and administration of Medicare Local coverage determinations (LCDs). Learn more about the LCD Modernization Process effective January 1, 2019

What is the CAC Network?

The ACR CAC Network was developed to encourage communication and coordination among all radiology CAC representatives. The ACR is committed to providing as much assistance as possible to each CAC representative. Adoption of the ACR CAC Networks and the model by the state chapters created a more organized and effective mechanism for dealing with local Medicare issues. State Chapter leaders should notify ACR staff of changes to CAC representatives and alternates.

For questions regarding the CAC Network at the ACR, please contact Alicia Blakey.

CMS Coverage Resources

Additional Resources

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Imaging 3.0


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