Key facts for NCD 190.21
- Benefit category
- Diagnostic Laboratory Tests
- Effective date
- 11/25/2002
- Implemented 01/01/2003
- Transmittal
- Transmittal 17
- Versions published
- 1
- Manual chapter
- 190
- NCD Manual (Pub. 100-03)
- Lab edit list
- 1,323 covered ICD-10
- 490 non-covered
TL;DR
NCD 190.21 sets Medicare's national policy for glycated hemoglobin/glycated protein under the benefit category "Diagnostic Laboratory Tests", effective 11/25/2002 and implemented 01/01/2003. Glycated hemoglobin/protein testing is widely accepted as medically necessary for the management and control of diabetes. It is also valuable to assess hyperglycemia, a history of hyperglycemia or dangerous hypoglycemia. Glycated protein testing may be used… As a laboratory NCD it carries a national ICD-10 edit list: 1,323 diagnosis codes support medical necessity and 490 are denied, applied automatically by every Medicare contractor to 2 procedure codes.
Item or service described
The management of diabetes mellitus requires regular determinations of blood glucose levels. Glycated hemoglobin/protein levels are used to assess long-term glucose control in diabetes. Alternative names for these tests include glycated or glycosylated hemoglobin or Hgb, hemoglobin glycated or glycosylated protein, and fructosamine.
Glycated hemoglobin (equivalent to hemoglobin A1) refers to total glycosylated hemoglobin present in erythrocytes, usually determined by affinity or ion-exchange chromatographic methodology. Hemoglobin A1c refers to the major component of hemoglobin A1, usually determined by ion-exchange affinity chromatography, immunoassay or agar gel electrophoresis. Fructosamine or glycated protein refers to glycosylated protein present in a serum or plasma sample. Glycated protein refers to measurement of the component of the specific protein that is glycated usually by colorimetric method or affinity chromatography.
Glycated hemoglobin in whole blood assesses glycemic control over a period of 4-8 weeks and appears to be the more appropriate test for monitoring a patient who is capable of maintaining long-term, stable control. Measurement may be medically necessary every 3 months to determine whether a patient's metabolic control has been on average within the target range. More frequent assessments, every 1-2 months, may be appropriate in the patient whose diabetes regimen has been altered to improve control or in whom evidence is present that intercurrent events may have altered a previously satisfactory level of control (for example, post-major surgery or as a result of glucocorticoid therapy). Glycated protein in serum/plasma assesses glycemic control over a period of 1-2 weeks. It may be reasonable and necessary to monitor glycated protein monthly in pregnant diabetic women. Glycated hemoglobin/protein test results may be low, indicating significant, persistent hypoglycemia, in nesidioblastosis or insulinoma, conditions which are accompanied by inappropriate hyperinsulinemia. A below normal test value is helpful in establishing the patient's hypoglycemic state in those conditions.
Indications and limitations of coverage
Indications
Glycated hemoglobin/protein testing is widely accepted as medically necessary for the management and control of diabetes. It is also valuable to assess hyperglycemia, a history of hyperglycemia or dangerous hypoglycemia. Glycated protein testing may be used in place of glycated hemoglobin in the management of diabetic patients, and is particularly useful in patients who have abnormalities of erythrocytes such as hemolytic anemia or hemoglobinopathies.
Limitations
It is not considered reasonable and necessary to perform glycated hemoglobin tests more often than every three months on a controlled diabetic patient to determine whether the patient's metabolic control has been on average within the target range. It is not considered reasonable and necessary for these tests to be performed more frequently than once a month for diabetic pregnant women. Testing for uncontrolled type one or two diabetes mellitus may require testing more than four times a year. The above Description Section provides the clinical basis for those situations in which testing more frequently than four times per annum is indicated, and medical necessity documentation must support such testing in excess of the above guidelines.
Many methods for the analysis of glycated hemoglobin show significant interference from elevated levels of fetal hemoglobin or by variant hemoglobin molecules. When the glycated hemoglobin assay is initially performed in these patients, the laboratory may inform the ordering physician of a possible analytical interference. Alternative testing, including glycated protein, for example, fructosamine, may be indicated for the monitoring of the degree of glycemic control in this situation. It is therefore conceivable that a patient will have both a glycated hemoglobin and glycated protein ordered on the same day. This should be limited to the initial assay of glycated hemoglobin, with subsequent exclusive use of glycated protein. These tests are not considered to be medically necessary for the diagnosis of diabetes.
Note: Scroll down for links to the quarterly Covered Code Lists (including narrative).
Text reproduced from the CMS Medicare Coverage Database record for NCD 190.21 version 1. View the original on cms.gov.
Laboratory NCD code lists (January 2026)
Medicare contractors apply this NCD through a national edit: the procedure codes below are paid only when the claim carries a covered diagnosis. The January 2026 list holds 1,323 covered and 490 non-covered ICD-10-CM codes plus 98 codes with other resolution rules.
2 procedure codes are edited against this NCD's diagnosis list. CPT codes are shown as numbers only; descriptors are licensed by the AMA.
| Code | Code set |
|---|---|
| 82985 | CPT (descriptor licensed by AMA) |
| 83036 | CPT (descriptor licensed by AMA) |
The first 40 of 1,323 covered diagnosis codes, with FY2027 ICD-10-CM descriptions. A claim with any covered code on the line supports medical necessity under the national edit.
| ICD-10-CM | Description | Effective |
|---|---|---|
| D137 | Benign neoplasm of endocrine pancreas | 2015-10-01 |
| E0800 | Diabetes mellitus due to underlying condition with hyperosmolarity without nonketotic hyperglycemic-hyperosmolar coma (NKHHC) | 2015-10-01 |
| E0801 | Diabetes mellitus due to underlying condition with hyperosmolarity with coma | 2015-10-01 |
| E0810 | Diabetes mellitus due to underlying condition with ketoacidosis without coma | 2015-10-01 |
| E0811 | Diabetes mellitus due to underlying condition with ketoacidosis with coma | 2015-10-01 |
| E0821 | Diabetes mellitus due to underlying condition with diabetic nephropathy | 2015-10-01 |
| E0822 | Diabetes mellitus due to underlying condition with diabetic chronic kidney disease | 2015-10-01 |
| E0829 | Diabetes mellitus due to underlying condition with other diabetic kidney complication | 2015-10-01 |
| E08311 | Diabetes mellitus due to underlying condition with unspecified diabetic retinopathy with macular edema | 2015-10-01 |
| E08319 | Diabetes mellitus due to underlying condition with unspecified diabetic retinopathy without macular edema | 2015-10-01 |
| E08321 | — | 2015-10-01 |
| E083211 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy with macular edema, right eye | 2016-10-01 |
| E083212 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy with macular edema, left eye | 2016-10-01 |
| E083213 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy with macular edema, bilateral | 2016-10-01 |
| E083219 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy with macular edema, unspecified eye | 2016-10-01 |
| E08329 | — | 2015-10-01 |
| E083291 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy without macular edema, right eye | 2016-10-01 |
| E083292 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy without macular edema, left eye | 2016-10-01 |
| E083293 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy without macular edema, bilateral | 2016-10-01 |
| E083299 | Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy without macular edema, unspecified eye | 2016-10-01 |
| E08331 | — | 2015-10-01 |
| E083311 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy with macular edema, right eye | 2016-10-01 |
| E083312 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy with macular edema, left eye | 2016-10-01 |
| E083313 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy with macular edema, bilateral | 2016-10-01 |
| E083319 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy with macular edema, unspecified eye | 2016-10-01 |
| E08339 | — | 2015-10-01 |
| E083391 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy without macular edema, right eye | 2016-10-01 |
| E083392 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy without macular edema, left eye | 2016-10-01 |
| E083393 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy without macular edema, bilateral | 2016-10-01 |
| E083399 | Diabetes mellitus due to underlying condition with moderate nonproliferative diabetic retinopathy without macular edema, unspecified eye | 2016-10-01 |
| E08341 | — | 2015-10-01 |
| E083411 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy with macular edema, right eye | 2016-10-01 |
| E083412 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy with macular edema, left eye | 2016-10-01 |
| E083413 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy with macular edema, bilateral | 2016-10-01 |
| E083419 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy with macular edema, unspecified eye | 2016-10-01 |
| E08349 | — | 2015-10-01 |
| E083491 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy without macular edema, right eye | 2016-10-01 |
| E083492 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy without macular edema, left eye | 2016-10-01 |
| E083493 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy without macular edema, bilateral | 2016-10-01 |
| E083499 | Diabetes mellitus due to underlying condition with severe nonproliferative diabetic retinopathy without macular edema, unspecified eye | 2016-10-01 |
490 diagnosis codes deny automatically under this NCD; the first 20 are shown.
| ICD-10-CM | Description |
|---|---|
| R99 | Ill-defined and unknown cause of mortality |
| Z0000 | Encounter for general adult medical examination without abnormal findings |
| Z0001 | Encounter for general adult medical examination with abnormal findings |
| Z00110 | Health examination for newborn under 8 days old |
| Z00111 | Health examination for newborn 8 to 28 days old |
| Z00121 | Encounter for routine child health examination with abnormal findings |
| Z00129 | Encounter for routine child health examination without abnormal findings |
| Z005 | Encounter for examination of potential donor of organ and tissue |
| Z006 | Encounter for examination for normal comparison and control in clinical research program |
| Z0070 | Encounter for examination for period of delayed growth in childhood without abnormal findings |
| Z0071 | Encounter for examination for period of delayed growth in childhood with abnormal findings |
| Z008 | Encounter for other general examination |
| Z020 | Encounter for examination for admission to educational institution |
| Z021 | Encounter for pre-employment examination |
| Z022 | Encounter for examination for admission to residential institution |
| Z023 | Encounter for examination for recruitment to armed forces |
| Z024 | Encounter for examination for driving license |
| Z025 | Encounter for examination for participation in sport |
| Z026 | Encounter for examination for insurance purposes |
| Z0271 | Encounter for disability determination |
Revision history
07/2004 - Published NCD in the NCD Manual without change to narrative contained in PM AB-02-110. Coding guidance now published in Medicare Lab NCD Manual. Effective and Implementation dates NA. ( TN 17 ) (CR 2130)
07/2002 - Implemented NCD. Effective date 11/25/02. Implementation date 1/01/03. ( TN AB-02-110 ) (CR 2130)
How this NCD shows up on remittances
A service denied under a National Coverage Determination returns CARC 50 (not deemed medically necessary) with remark N386 (decision based on an NCD); a denial citing a local policy instead carries N115. Because NCDs bind nationally, the appeal path is documentation that the patient meets the indications above, not a contractor-policy argument.
How QuickIntell applies NCD 190.21
QuickAuth checks the ordered service and diagnosis against NCD and LCD criteria before the encounter, QuickCode validates the diagnosis pairing on the claim, and QuickRCM routes CARC 50 denials with the policy text and the covered-code list attached so the appeal starts with evidence.
Frequently asked questions — NCD 190.21
What does NCD 190.21 cover?
Glycated hemoglobin/protein testing is widely accepted as medically necessary for the management and control of diabetes. It is also valuable to assess hyperglycemia, a history of hyperglycemia or dangerous hypoglycemia. Glycated protein testing may be used in place of glycated hemoglobin in the management of diabetic patients, and is particularly useful in patients who have abnormalities of erythrocytes such as… The full indications and limitations are reproduced on this page from the CMS Medicare Coverage Database.
When did NCD 190.21 take effect?
The current version (1) is effective 11/25/2002, implemented 01/01/2003, published in transmittal 17. This is the only published version.
Does a Local Coverage Determination override NCD 190.21?
No. A National Coverage Determination binds all Medicare Administrative Contractors; an LCD can only address services or circumstances the NCD leaves open. Claims denied under this NCD typically return CARC 50 with remark N386 (NCD) rather than N115 (LCD).
Which diagnosis codes are covered under NCD 190.21?
The January 2026 laboratory NCD edit list contains 1,323 ICD-10-CM codes that support glycated hemoglobin/glycated protein (for example D137 Benign neoplasm of endocrine pancreas; E0800 Diabetes mellitus due to underlying condition with hyperosmolarity without nonketotic hyperglycemic-hyperosmolar coma (NKHHC); E0801 Diabetes mellitus due to underlying condition with hyperosmolarity with coma) and 490 codes that deny. The list applies to 82985, 83036.
How often does the lab NCD code list for 190.21 change?
CMS updates the laboratory NCD edit module quarterly, with the January release carrying the annual ICD-10-CM code changes. Codes added or deleted mid-year appear in the quarterly change spreadsheets on the Lab NCDs page.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-02. Verify against the primary file before billing or contracting decisions.
- Medicare Coverage Database NCDs via the CMS Coverage APIVersion API snapshot 2026-09-27 · effective 2026-09-20 · file national-coverage-ncd.jsonSHA-256 a90fadfd264b9ef4…
- Laboratory NCD ICD-10 code lists, January 2026Version January 2026 · effective 2026-01-01 · file 2026100-Initial-ICD10-NCD-Spreadsheet-20250721-508.xlsxSHA-256 57ff5cd37ba523d3…
- ICD-10-CM FY2027 code descriptionsVersion FY2027 · effective 2026-10-01 · file icd10cm_codes_2027.txtSHA-256 3c0583a38ee0e848…
Disclaimer
This page reproduces the CMS National Coverage Determination text and, for laboratory NCDs, the CMS ICD-10 edit lists, as an operational reference. Coverage decisions depend on the full policy, the claim and the contractor; nothing here is legal, clinical or billing advice. CPT codes are shown as numbers only; CPT descriptors are copyright AMA.