Key facts for NCD 160.21
- Benefit category
- Incident to a physician's professional Service, Physicians' Services
- Effective date
- This is a longstanding national coverage determination. The effective date of this version has not been posted.
- Transmittal
- n/a
- Versions published
- 1
- Manual chapter
- 160
- NCD Manual (Pub. 100-03)
TL;DR
NCD 160.21 sets Medicare's national policy for telephone transmission of eegs under the benefit category "Incident to a physician's professional Service, Physicians' Services", effective This is a longstanding national coverage determination. The effective date of this version has not been posted.. Telephone transmission of EEGs is covered as a physician's service or as incident to a physician's service when reasonable and necessary for the individual patient, under appropriate circumstances. The service is safe, and may save time and cost in sending… It has been revised once since publication and binds every Medicare Administrative Contractor nationally.
Item or service described
Telephone transmission of EEGs has been most helpful in the following clinical situations:
• Altered consciousness, such as stuporous, semicomatose, or comatose states;
• Atypical seizure variants in patients experiencing bizarre, distressing symptoms as seen with "spike and wave stupor" or other forms of seizure disorders;
• Diagnosis of a suspected intracranial tumor;
• Head injury, where a subdural hematoma may be identified;
• Headaches during the acute phase where, for instance, in migraine syndrome, abnormal responses may be seen.
Telephonically transmitted EEGs should not be used for determining electrical inactivity (i.e., brain death), because of unavoidable signal interference.
Indications and limitations of coverage
Telephone transmission of EEGs is covered as a physician's service or as incident to a physician's service when reasonable and necessary for the individual patient, under appropriate circumstances. The service is safe, and may save time and cost in sending EEGs from remote areas without special competence in neurology, neurosurgery, and electroencephalography, by avoiding the need to transport patients to large medical centers for standard EEG testing.
Text reproduced from the CMS Medicare Coverage Database record for NCD 160.21 version 1. View the original on cms.gov.
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 160.21
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 160.21
What does NCD 160.21 cover?
Telephone transmission of EEGs is covered as a physician's service or as incident to a physician's service when reasonable and necessary for the individual patient, under appropriate circumstances. The service is safe, and may save time and cost in sending EEGs from remote areas without special competence in neurology, neurosurgery, and electroencephalography, by avoiding the need to transport patients to large… The full indications and limitations are reproduced on this page from the CMS Medicare Coverage Database.
When did NCD 160.21 take effect?
The current version (1) is effective This is a longstanding national coverage determination. The effective date of this version has not been posted.. This is the only published version.
Does a Local Coverage Determination override NCD 160.21?
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).
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…
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.