US · guidance
CMS Pub. 100-04, ch. 4, § 250.9.3
Assistant at Surgery Medicare Summary Notice (MSN) and
Remittance Advice (RA) Messages
(Rev. 3475, Issued: 03-04-16, Effective: 06-06-16, Implementation: 06-06-16)
Contractors shall deny medically unnecessary assistant at surgery services for
HCPCS/CPT codes with a payment policy indicator of ‘0’ or ‘2’ when an Advance
Beneficiary Notice (ABN) was issued.
The contractor shall use the following remittance advice messages and associated codes
when rejecting/denying claims under this policy. This CARC/RARC combination is
compliant with CAQH CORE Business Scenario Three.
Group Code: PR
CARC: 54
RARC: N/A
MSN: 36.1
Contractors shall deny medically unnecessary assistant at surgery services for
HCPCS/CPT codes with a payment policy indicator of ‘0’ or ‘2’ when an ABN was not
issued.
The contractor shall use the following remittance advice messages and associated codes
when rejecting/denying claims under this policy. This CARC/RARC combination is
compliant with CAQH CORE Business Scenario Three.
Group Code: CO
CARC: 54
RARC: N/A
MSN: 36.2
Contractors shall deny assistant at surgery services for HCPCS/CPT codes with a
payment policy indicator of ‘1’.
The contractor shall use the following remittance advice messages and associated codes
when rejecting/denying claims under this policy. This CARC/RARC combination is
compliant with CAQH CORE Business Scenario Three.
Group Code: CO
CARC: 54
RARC: N/A
MSN: 15.11
History
(Rev. 3475, Issued: 03-04-16, Effective: 06-06-16, Implementation: 06-06-16)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
202da0856af3f572ef4cd1c2a42c79ff132d7c200af71c4bc4718e8cc335e619
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