US · guidance
CMS Pub. 100-04, ch. 23, § 80.5.1
Use of Relative Value Scale and Conversion Factors for
Reasonable Charge Gap-Filling
(Rev. 1, 10-01-03)
B3-5022.1
The relative value scales used to fill gaps in charge data for the Medicare program should,
to the extent possible, be those that contractors use in their own programs. Relative value
scales developed by contractors or by medical societies for States other than those in which
your Medicare service area is located should be carefully reviewed and validated before
they are used. Ensure that a relative value scale, which is used to estimate customary
charges or prevailing charges, accurately reflects charge patterns in the area you service.
Similarly, the conversion factor used with the relative value scale should reflect the known
customary charges of the physician or other person for whom a customary charge is being
estimated, or the known prevailing charges for services in the locality, as appropriate.
As a result of consent agreements with the Federal Trade Commission (FTC), relative
value scales formerly published by the American Academy of Orthopedic Surgeons, the
American College of Obstetricians and Gynecologists, the American College of Radiology,
and the California Medical Association have been withdrawn from circulation. The FTC
consent agreements did not bar the use of the related procedural terminology and coding
systems. However, do not use these four relative value scales to fill gaps in customary and
prevailing charge data.
This does not mean that you must discontinue using relative value scales to fill gaps in
customary charges or in determining prevailing charges. Instead use a system of relative
value units that has not been the subject of a consent agreement, or develop your own
system. A potential source of information in this regard is the relative value scale that has
been included with the CMS HCPCS. This relative value scale is included with HCPCS as
an informational item only. You may use it, revise it, or use some other relative value scale
if you deem it more appropriate.
You may, if necessary develop a relative value scale for gap-filling purposes by dividing
the unadjusted prevailing charges in a locality by a common denominator and filling the
gaps in the resulting “relative value scale” by relying on medical staff judgment or on other
persons with knowledge of the charging patterns and practices in your service area.
Alternatively, you may use a service area wide approach and/or the unweighted average of
the customary charges that have been made for a service, divided by a common
denominator.
For radiology codes (codes beginning with 7, local radiology codes, and R-codes in
HCPCS), you may use the national and local relative values used to make payment under
the radiology fee schedule.
Customary and/or prevailing charge conversion factors used with relative value scales to
fill gaps in reasonable charge screens should be calculated as outlined in A and B below.
(Develop separate customary charge conversion factors for each physician or supplier from
his known customary charges in the same category of services, e.g., medicine, surgery,
radiology, etc. Similarly, separate prevailing charge conversion factors, by locality (and by
specialty or groups of specialties as applicable), should be calculated based on the known
prevailing charges, by locality and specialty, or groups of specialties within the same
category of service. Customary charge conversion factors may only be calculated for a
physician for a category of service if the physician has at least seven customary charges for
services in that category of service upon which to base the conversion factor calculation. If
a physician does not have sufficient customary charges to calculate a conversion factor in
one category of service, this does not preclude the calculation of his customary charge
conversion factors for other categories of service for which he does have sufficient
customary charges).
A. Customary Charge
Use the following formula for the calculation of a customary charge conversion factor:
C/F = Customary charge conversion factor
CHG = The physician’s customary charge for a procedure
SVC = Number of times the physician performed the procedure
l-n = The different procedures the physician performed within a category of service
RVU = The relative value unit assigned to a procedure
SIGMA = Sum of
C/F = CHG1
RVUl x SVCl + CHG2
RVU2 x SVC2 .CHGn
RVUn x SVCn
_________________________________________________
SIGMA SVC1-n
EXAMPLE: Compute a customary charge conversion factor for a physician with the
following charge history: (May be for medicine, surgery, radiology, pathology.)
Procedure Frequency Customary Charge Relative Value
1 $ 3 5.00 1
2 7 12.00 2
3 5 35.00 4
4 4 20.00 3
5 6 8.00 1.5
25
Method
l. For each procedure, divide the customary charge by the relative value and multiply the
result by the frequency of that procedure in the physician’s charge history.
2. Add all the results of these computations.
3. Divide the result by the sum of all the frequencies.
Solution
(5x3)
1 + (12x7)
2 + (35x5)
4 + (20x4)
3 + (8x6
1.5 divided by 25=
(5 x 3) + (6 x 7) + (8.75 x 5) + (6.67 x 4) + (5.33 x 6) = 25
15 + 42 + 43.75 + 26.68 + 3l.98 = 25
159.41 = $6.40 (i.e., $6.38 rounded to the 25 nearest 10 cents)
To determine a physician’s customary charge for a particular procedure where there is no
reliable statistical basis, multiply the relative value of the procedure by the physician’s
customary charge conversion factor for the appropriate category of service (e.g., radiology,
medicine, surgery).
B. Prevailing Charges
The prevailing charge conversion factors used with the appropriate relative value scale are
developed from the same formula used for customary charge conversion factors, except
that:
CHG = The fully adjusted locality prevailing charge for a procedure by locality and
by specialty or group of specialties (regardless of the source of data from which the
locality prevailing charge was developed).
SVC = The number of times the procedure was performed by all physicians in the
same specialty or group of specialties and locality.
l-n = The different procedures within a category of service for which prevailing
charges have been established by specialty or group of specialties and locality.
The conversion factors calculated for any fee screen year reflect customary and prevailing
charges calculated on the basis of charge data for the year ending June 30 immediately
preceding the start of the fee screen year. Also, reasonable charge screens established
through the use of a relative value scale and conversion factors consist of two components.
Consequently, the conversion factors must be recalculated when there is any change in the
relative value units assigned to procedures (as may occur if you use a different or updated
relative value scale) in order to assure that the change(s) in unit values do not violate the
integrity of the reasonable charge screens. The economic index limitation, the no rollback
provision, and the Administrative Savings Clause are not applied directly to prevailing
charge conversion factors calculated in accordance with this section.
80.6 - Inflation Indexed Charge (IIC) for Nonphysician Services
(Rev. 2837, Issued: 12-13-13, Effective: 01-01-14 - payment reasonable charge basis/04-01-14 - payment national fee schedule basis, Implementation: 01-06-14 - payment reasonable charge basis/04-07-14 - payment national fee schedule basis)
A General
Effective for services rendered on or after October 1, 1985, an additional factor - the
inflation indexed charge (IIC), is added to the factors taken into consideration in
determining reasonable charges for non-physician services. Non-physician services are
defined as those Part B medical services, supplies, and equipment reimbursed on a
reasonable charge basis and not subject to the application of the Medicare Economic Index
(MEI).
Examples of items affected by the IIC are:
• Prosthetic and orthotic devices not subject to the fee schedules [Therapeutic Shoes
(2005 and prior), Intraocular Lenses (2014 and prior)];
• Blood products and transfusion medicine;
• Certain medical supplies used in connection with home dialysis (2011 and prior);
and
• Ambulance services (2001 and prior)
History
(Rev. 1, 10-01-03)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
521717785da3ad5db40e96779bd0e33fdc8cc9edd8a95cb636c44cf3b8a870b7
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