Local Coverage Article Billing and Coding

Billing and Coding: GlycoMark® Testing for Glycemic Control


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Article Information

General Information

Article ID
Article Title
Billing and Coding: GlycoMark® Testing for Glycemic Control
Article Type
Billing and Coding
Original Effective Date
Revision Effective Date
Revision Ending Date
Retirement Date
AMA CPT / ADA CDT / AHA NUBC Copyright Statement

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CMS National Coverage Policy

Title XVIII of the Social Security Act, §1833(e). Prohibits Medicare payment for any claim which lacks the necessary information to process the claim.

CMS Internet-Only Manuals, Publication 100-04, Medicare Claims Processing Manual, Chapter 16, §50.5 Jurisdiction of Laboratory Claims, 60.12 Independent Laboratory Specimen Drawing, 60.2. Travel Allowance.

CMS Internet Online Manual Pub. 100-04 (Medicare Claims Processing Manual), Chapter 23 (Section 10) "Reporting ICD Diagnosis and Procedure Codes"

Article Guidance

Article Text

The information in this article contains billing, coding or other guidelines that complement the local coverage policy for L36906-GlycoMark® Testing for Glycemic Control.


To receive a GlycoMark® test denial, please submit the following claim information:


  • CPT® code 84378 or 84999
  • An Advance Beneficiary Notice (ABN) is not required for statutorily excluded services
    • For a voluntary issued ABN, append with GX modifier
    • To indicate a statutorily excluded service, append with a GY modifier


General Guidelines for Claims submitted to Part A or Part B MAC:

Procedure codes may be subject to National Correct Coding Initiative (NCCI) edits or OPPS packaging edits. Refer to NCCI and OPPS requirements prior to billing Medicare. For services requiring a referring/ordering physician, the name and NPI of the referring/ordering physician must be reported on the claim. A claim submitted without a valid ICD-10-CM diagnosis code will be returned to the provider as an incomplete claim under Section 1833(e) of the Social Security Act. The diagnosis code(s) must best describe the patient's condition for which the service was performed. For diagnostic tests, report the result of the test if known; otherwise the symptoms prompting the performance of the test should be reported.


Advance Beneficiary Notice of Non-coverage (ABN) Modifier Guidelines

An ABN may be used for services which are likely to be non-covered, whether for medical necessity or for other reasons. Refer to CMS Publication 100-04, Medicare Claims Processing Manual, Chapter 30, for complete instructions.

Effective from April 1, 2010, non-covered services should be billed with modifier –GA, -GX, -GY, or –GZ, as appropriate.

The –GA modifier (“Waiver of Liability Statement Issued as Required by Payer Policy”) should be used when physicians, practitioners, or suppliers want to indicate that they anticipate that Medicare will deny a specific service as not reasonable and necessary and they do have an ABN signed by the beneficiary on file. Modifier GA applies only when services will be denied under reasonable and necessary provisions, sections 1862(a)(1), 1862(a)(9), 1879(e), or 1879(g) of the Social Security Act. Effective April 1, 2010, Part A MAC systems will automatically deny services billed with modifier GA. An ABN, Form CMS-R-131, should be signed by the beneficiary to indicate that ‎he/she accepts responsibility for payment.‎ The -GA modifier may also be used on assigned claims when a patient refuses to sign the ABN and the latter is properly witnessed. For claims submitted to the Part A MAC, occurrence code 32 and the date of the ABN is required.


Modifier GX (“Notice of Liability Issued, Voluntary Under Payer Policy”) should be used when the beneficiary has signed an ABN, and a denial is anticipated based on provisions other than medical necessity, such as statutory exclusions of coverage or technical issues. An ABN is not required for these denials, but if non-covered services are reported with modifier GX, will automatically be denied services.


The –GZ modifier should be used when physicians, practitioners, or suppliers want to indicate that they expect that Medicare will deny an item or service as not reasonable and necessary and they have not had an ABN signed by the beneficiary. ‎If the service is statutorily non-covered, or without a benefit category, submit the ‎appropriate CPT/HCPCS code with the -GY modifier. An ABN is not required for these denials, and the limitation of liability does not apply for beneficiaries. Services with modifier GY will automatically deny.

Documentation Requirements

The patient’s medical record should include but is not limited to:

  • The assessment of the patient by the ordering provider as it relates to the complaint of the patient for that visit,
  • Relevant medical history
  • Results of pertinent tests/procedures
  • Signed and dated office visit record/operative report (Please note that all services ordered or rendered to Medicare beneficiaries must be signed.)



Coding Information


Group 1

(2 Codes)
Group 1 Paragraph


Group 1 Codes

CPT/HCPCS Modifiers

Group 1

(2 Codes)
Group 1 Paragraph


Group 1 Codes

ICD-10-CM Codes that Support Medical Necessity


ICD-10-CM Codes that DO NOT Support Medical Necessity


ICD-10-PCS Codes


Additional ICD-10 Information


Bill Type Codes

Contractors may specify Bill Types to help providers identify those Bill Types typically used to report this service. Absence of a Bill Type does not guarantee that the article does not apply to that Bill Type. Complete absence of all Bill Types indicates that coverage is not influenced by Bill Type and the article should be assumed to apply equally to all claims.


Revenue Codes

Contractors may specify Revenue Codes to help providers identify those Revenue Codes typically used to report this service. In most instances Revenue Codes are purely advisory. Unless specified in the article, services reported under other Revenue Codes are equally subject to this coverage determination. Complete absence of all Revenue Codes indicates that coverage is not influenced by Revenue Code and the article should be assumed to apply equally to all Revenue Codes.


Other Coding Information


Revision History Information

Revision History DateRevision History NumberRevision History Explanation
03/02/2023 R6

Revision Effective: 03/02/2023

Revision Explanation: Annual review, no changes were made.

02/10/2022 R5

Revision Effective: 02/10/2022

Revision Explanation: Annual review, added trademark symbol where needed.

03/25/2021 R4

Revision Effective: 03/25/2021

Revision Explanation: Annual review, no chnages were made.

10/31/2019 R3

Revision Effective: n/a

Revision Explanation: Annual Review, no changes made.

10/31/2019 R2


Revision Effective: 10/31/2019

Revision Explanation: This article is being revised in order to adhere to CMS requirements per chapter 13, section 13.5.1 of the Program Integrity Manual, to remove all coding from LCDs and incorporate into related Billing and Coding Articles. Regulations regarding billing and coding were removed from the CMS National Coverage Policy section of the related GlycoMark Testing for Glycemic Control LCD and placed in this article. Under CPT/HCPCS Modifiers added modifier GX and GY.

09/12/2019 R1


Revision Effective: 09/19/2019

Revision Explanation: Converted article into new Billing and Coding template no other changes made.

Associated Documents

Related Local Coverage Documents
Related National Coverage Documents
Statutory Requirements URLs
Rules and Regulations URLs
CMS Manual Explanations URLs
Other URLs
Public Versions
Updated On Effective Dates Status
02/20/2023 03/02/2023 - N/A Currently in Effect You are here
02/02/2022 02/10/2022 - 03/01/2023 Superseded View
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