CurrentMass General Brigham Health PlanPolicy N/A

Acute Hospital Care at Home — Reimbursement and Authorization Requirements

Defines Mass General Brigham Health Plan's reimbursement, billing, and authorization requirements for Acute Hospital Care at Home services provided by CMS-approved hospitals and the affected members and facilities.

Policy Summary

PayerMass General Brigham Health Plan

PolicyAcute Hospital Care at Home — Reimbursement and Authorization Requirements

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateN/A

Next Review DateN/A

Key ActionObtain prior authorization for all facility inpatient services, including Acute Hospital Care at Home.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

Prior authorization requiredfacility inpatient services prerequisite

0161Hospital at home revenue code

No separate reimbursementhome ancillary services

APR-DRG / MS-DRGreimbursement methodology

POS 12professional claims POS

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Coverage rules and exclusions

Coverage criteria and exclusions

Covered when ALL of the following are met:

ALL of the following

The service is provided by a CMS‑approved Acute Hospital at Home participating hospital (per CMS program approvals).
The member is transferred from the emergency department and/or observation status or inpatient acute floor to the Acute Hospital at Home program.
The condition for which Acute Hospital Care at Home is provided is one of the conditions approved and defined by CMS.
Prior authorization has been obtained (Mass General Brigham Health Plan requires prior authorization for all facility inpatient services, including Acute Hospital Care at Home).
Reimbursement methodology by line of business
- MassHealth members: reimbursement per APR‑DRG methodology.
- Commercial/ASO and Medicare Advantage members: reimbursement per MS‑DRG methodology.

Facility professional claims for hospital‑employed providers delivering acute inpatient services at home should use Place of Service 12 where applicable.

Billing must follow provider payment guidelines including use of hospital at home revenue code 0161 (effective for claims received on or after July 1, 2022) where applicable.

Room and board charges represent a full 24‑hour calendar day; emergency room charges or observation bed hours are not separately reimbursed when billed with Acute Hospital Care at Home transfers.

Exclusions (services not reimbursed)

Related services rendered in the home (ancillary services) are not separately billed and will not be reimbursed outside of the all‑encompassing rate.
Interim or late billing charges for claims reimbursed based on APR‑DRG or other DRG methodologies are not reimbursable.
Experimental, investigational, and/or cosmetic services are excluded; authorization for an inpatient admission does not override these coverage limits.

Approval and reimbursement for approved facilities will follow line‑of‑business specific guidance: Commercial and Medicare Advantage align with Massachusetts DOI Bulletin or MassHealth guidance; MassHealth follows MassHealth Acute Inpatient Hospital Bulletin 180.

Billing codes, place of service, and DRG reimbursement

Billing codes and place of serviceRevenue | Modifier | CPTCovered

0161	Hospital at home, R&B/hospital at home (effective for claims received on or after July 1, 2022)
0119	Room and Board, Private Other (note: not to be used for Acute Hospital Care at Home as of specified date)
POS 12	Place of Service 12 - patient private residence for professional claims

DRG groupers for inpatient reimbursementmixedCovered

APR-DRG	All Patient Refined Diagnosis Related Groups used for MassHealth (Medicaid) members
MS-DRG	Medicare Severity DRG used for Commercial and Medicare Advantage members

APR-DRG per diem conversion

FormulaAPR-DRG per diem = Base Rate * APR-DRG weight / Network Average Length of Stay

Base RateApplied base payment rate used in the per diem calculation

APR-DRG weightThe diagnosis-related group weight from the APR-DRG grouper used for the member population

Network Average Length of StayDenominator for per diem conversion reflecting network-average LOS for the APR-DRG

MS-DRG per diem conversion

FormulaMS-DRG per diem = Base Rate * MS-DRG weight / Arithmetic Geometric Mean Length of Stay

Base RateApplied base payment rate used in the per diem calculation

MS-DRG weightThe diagnosis-related group weight from the MS-DRG grouper used for Commercial and Medicare Advantage members

Arithmetic Geometric Mean Length of StayDenominator for per diem conversion using the arithmetic geometric mean LOS for the MS-DRG

Authorization and provider requirements

Prior Authorization

Prior authorization required for all facility inpatient services (includes Hospital at Home)

Prior authorization is required for all facility inpatient services, including Acute Hospital Care at Home; services are covered only for conditions approved and defined by CMS.

Member must transfer from the emergency room and/or observation status, inpatient acute to qualify for Acute Hospital at Home services.
Emergency room charges or observation bed hours are not separately reimbursed when Room and Board charges apply.

Key definitions

Acute Hospital at Home

DefinitionHospital-level care provided in the patient’s home to acutely ill members who meet InterQual criteria and are part of CMS-approved Acute Hospital at Home programs.

Referral pathwayMembers are referred from the emergency department or an inpatient acute floor to the Acute Hospital at Home care option.

Coverage requirementCovered and reimbursed only for hospitals that have been approved by CMS as part of their Acute Hospital at Home program.

InterQual criteriaPatients must meet InterQual criteria for Acute Hospital at Home services to qualify for this model of care.

Place of Service 12

Place of Service 12 meaningDesignates services provided in a patient’s private residence (location other than a hospital or facility).

Use instructionUse POS 12 on professional (HCFA 1500) claims when hospital-employed providers bill for acute inpatient hospital services delivered in the patient’s home.

Billing contextThere is no separate reimbursement for home services provided by hospital-employed providers; POS 12 is for claim location reporting on professional claims.