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Insurance Structure

Insurance Payer (Company)
    └─ OFFERS
        └─ Insurance Plan (Product)
            └─ DEFINES
                └─ Medical Policy (Coverage Rules)
                    ├─ COVERS → Medical Code (Approved)
                    ├─ DOES_NOT_COVER → Medical Code (Excluded)
                    └─ REFERENCES → Medical Code (Mentioned)
  • Payer: Insurance company or organization (e.g., UnitedHealthcare, Cigna)
  • Plan: Specific insurance product offered by a payer
  • Plan Types:
    • commercial: Private employer-sponsored insurance
    • medicare_part_a: Medicare hospital insurance
    • medicare_part_b: Medicare medical insurance
    • medicare_advantage: Medicare managed care (Part C)
    • medicaid: State-federal public insurance
    • exchange: Affordable Care Act marketplace plans

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Medical Codes

US healthcare uses standardized coding systems to identify procedures, services, and diagnoses:
  • CPT (Current Procedural Terminology): 5-digit numeric codes for medical procedures and services
    • Use case: The primary standard for physician billing and reimbursement
    • Example: 19318 = Breast reduction
    • Maintained by American Medical Association (AMA)
  • HCPCS Level II (Healthcare Common Procedure Coding System): Alphanumeric codes for non-physician services, supplies and drugs not covered by CPT.
    • Use case: Ambulances, DME (medical equipment) and drugs.
    • Example: J1234 (Drug injection), E0607 (Blood glucose monitor)
  • ICD-10-CM (International Classification of Diseases, 10th Revision, Clinical Modification): Diagnosis codes describing a patient’s condition or disease.
    • Use case: Establishes medical necessity of a procedure.
    • Example: E11.9 (Type 2 diabetes mellitus without complications)

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Coverage Policies

Medical coverage policies provide guidance on whether a payer’s plan will reimburse a particular procedure. They can be seen as ‘rulebooks’. A typical medical coverage policy includes two key sections:
  1. Medical necessity criteria: These are the clinical conditions required for a procedure to be deemed reasonable.
  • Example: ‘A blepharoplasty is deemed medically necessary ONLY IF upper visual field loss is present AND botulinum toxin injections trialled first are unsuccessful.
  1. Coding logic: These are lists of procedural and diagnostic codes which are related to the policy.
  • These are CPT codes, HCPCS codes and ICD-10-CM codes.

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Policy-Code Relationships

The Penelope API models three types of relationships between policies and medical codes:
  • COVERS: Policy explicitly covers this code
    • The code is approved for reimbursement under the policy
    • Indicates the procedure/service is covered for reimbursement if it is medically necessary
  • DOES_NOT_COVER: Policy explicitly excludes this code
    • The code is denied or considered not medically necessary
    • May indicate experimental, investigational, or cosmetic procedures
  • REFERENCES: Code is mentioned in the policy without explicit coverage decision
    • Useful for understanding policy scope.

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Medicare Framework

Medicare policies (NCD, LCD, and LCA) represent the gold standard of US medical coverage. They are issued by the federal government and adhere to a strict hierarchy of authority.

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NCD (National Coverage Determination)

  • Issuer: CMS (Federal Centers for Medicare & Medicaid Services).
  • Scope: Nationwide.
  • Authority: Binding for all Medicare plans, including Medicare Advantage (Part C).
  • Function: NCDs set the baseline. If an NCD says “Covered,” no local contractor or MA plan can deny it based on medical necessity, provided that the clinical criteria are met.

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LCD (Local Coverage Determination)

  • Issuer: MACs (Medicare Administrative Contractors).
  • Scope: Regional (specific states/jurisdictions).
  • Authority: Applies in the absence of an NCD.
  • Function: LCDs fill the gaps left by NCDs. They provide the detailed ‘Medical Necessity’ logic for procedures that don’t have a national ruling.

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LCA (Local Coverage Article)

  • Issuer: MACs (attached to an LCD).
  • Function: The technical implementation guide.
  • Why it matters: While the LCD contains the text, the LCA contains the tables of CPT and ICD-10 codes. Both go hand in hand.
Note on Medicare Advantage (Part C). Medicare Advantage plans (managed by private payers like Humana or UHC) are legally required to furnish, at minimum, the same benefits as Original Medicare. This means they must adhere to NCDs and LCDs. They cannot apply internal criteria that are more restrictive than the NCD/LCD applicable to the beneficiary’s region.