Key facts for NCD 20.14
- Benefit category
- Diagnostic Tests (other)
- Effective date
- 11/15/1980
- Transmittal
- n/a
- Versions published
- 1
- Manual chapter
- 20
- NCD Manual (Pub. 100-03)
TL;DR
NCD 20.14 sets Medicare's national policy for plethysmography under the benefit category "Diagnostic Tests (other)", effective 11/15/1980. Medicare coverage is extended to those procedures listed in Category I below when used for the accepted medical indications mentioned above. The procedures in Category II are still considered experimental and are not covered at this time. Denial of claims… It has been revised once since publication and binds every Medicare Administrative Contractor nationally.
Item or service described
Plethysmography involves the measurement and recording (by one of several methods) of changes in the size of a body part as modified by the circulation of blood in that part.
Plethysmography is of value as a noninvasive technique for diagnostic, preoperative and postoperative evaluation of peripheral artery disease in the internal medicine or vascular surgery practice. It is also a useful tool for the preoperative podiatric evaluation of the diabetic patient or one who has intermittent claudication or other signs or symptoms indicative of peripheral vascular disease which have a bearing on the patient's candidacy for foot surgery.
The oldest form of plethysmography is the venous occlusive pneumoplethysmography. This method is cumbersome, time consuming, and requires considerable training to give useful, reproducible results. Nonetheless, in the setting of the hospital vascular laboratory, this technique is considered a reasonable and necessary procedure for the diagnostic evaluation of suspected peripheral arterial disease. It is unsuitable for routine use in the physician's office.
Recently, however, a number of other plethysmographic methods have been developed which make use of phenomena such as changes in electric impedance or changes in segmental blood pressure at constant volume to assess regional perfusion. Several of these methods have reached a level of development which makes them clinically valuable.
Indications and limitations of coverage
Medicare coverage is extended to those procedures listed in Category I below when used for the accepted medical indications mentioned above. The procedures in Category II are still considered experimental and are not covered at this time. Denial of claims because a noncovered procedure was used or because there was no medical indication for plethysmographic evaluation of any type should be based on §1862(a)(1) of the Act.
Category I - Covered
Segmental Plethysmography - Included under this procedure are services performed with a regional plethysmograph, differential plethysmograph, recording oscillometer, and a pulse volume recorder.
Electrical Impedance Plethysmography
Ultrasonic Measurement of Blood Flow (Doppler) - While not strictly a plethysmographic method, this is also a useful tool in the evaluation of suspected peripheral vascular disease or preoperative screening of podiatric patients with suspected peripheral vascular compromise. (See §50-7 for the applicable coverage policy on this procedure.)
Oculoplethysmography - See NCD on Noninvasive Tests of Carotid Function, § 20.17 .
Strain Gauge Plethysmography - This test is based on recording the non-pulsatile aspects of inflowing blood at various points on an extremity by a mercury-in-silastic strain gauge sensor. The instrument consists of a chart recorder, an automatic cuff inflation and deflation system, and a recording manometer.
Category II - Experimental
The following methods have not yet reached a level of development such as to allow their routine use in the evaluation of suspected peripheral vascular disease.
Inductance Plethysmography - This method is considered experimental and does not provide reproducible results.
Capacitance Plethysmography - This method is considered experimental and does not provide reproducible results.
Mechanical Oscillometry - This is a non-standardized method which offers poor sensitivity and is not considered superior to the simple measurement of peripheral blood pressure.
Photoelectric Plethysmography - This method is considered useful only in determining whether or not a pulse is present and does not provide reproducible measurements of blood flow.
Differential plethysmography, on the other hand, is a system which uses an impedance technique to compare pulse pressures at various points along a limb, with a reference pressure at the mid-brachial or wrist level. It is not clear whether this technique, as usually performed in the physician's office, meets the definition of plethysmography because quantitative measurements of blood flow are usually not made. It has been concluded, in any event, that the differential plethysmography system is a blood pulse recorder of undetermined value, which has the potential for significant overutilization. Therefore, reimbursement for studies done by techniques other than venous occlusive pneumoplethysmography should be denied, at least until additional data on these devices, including controlled clinical studies, become available.
Text reproduced from the CMS Medicare Coverage Database record for NCD 20.14 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 20.14
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 20.14
What does NCD 20.14 cover?
Medicare coverage is extended to those procedures listed in Category I below when used for the accepted medical indications mentioned above. The procedures in Category II are still considered experimental and are not covered at this time. Denial of claims because a noncovered procedure was used or because there was no medical indication for plethysmographic evaluation of any type should be based on §1862(a)(1) of… The full indications and limitations are reproduced on this page from the CMS Medicare Coverage Database.
When did NCD 20.14 take effect?
The current version (1) is effective 11/15/1980. This is the only published version.
Does a Local Coverage Determination override NCD 20.14?
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.