Plain-English definitions for the acronyms and jargon a patient encounters when disputing a medical bill. The LLM should use the canonical phrasing here when explaining things to patients.
AGB, Amounts Generally Billed. Under IRS § 501(r), a non-profit hospital may not charge a patient who qualifies for financial assistance more than the average amount it bills insured patients for the same care. Calculated by one of two methods set in 26 CFR § 1.501(r)-5. Critical: a FAP-eligible patient's bill is capped at AGB, not the chargemaster.
AOB, Assignment of Benefits. A form the patient signs (often buried in admission paperwork) directing the insurance company to pay the provider directly rather than reimbursing the patient. Standard practice and usually fine, but flag if a provider asserts the AOB gives them rights beyond billing the insurer.
ALJ, Administrative Law Judge. Level 3 of the Medicare appeal process. Hearings are typically telephonic. Disputed amount must meet a published threshold (~$190 in 2026).
Allowable / Allowed amount. The maximum amount a health plan will pay for a covered service. Usually less than the provider's charge. The difference between charge and allowed is either the contractual write-off (for in-network providers) or balance bill (for out-of-network).
Balance billing. The provider's practice of charging the patient for the difference between what they billed and what the insurer paid. Prohibited for emergency services, out-of-network ancillary at in-network facilities, and air ambulance under the federal No Surprises Act. Prohibited for ground ambulance in roughly a dozen states.
Bundling. Two related practices: (1) properly combining related procedures into a single billable service per CMS National Correct Coding Initiative edits, legitimate; (2) insurers improperly combining separately-billable procedures to pay for only one, improper. Dental insurers are notorious for the second.
Chargemaster. The hospital's master list of full-charge prices. Almost no one pays chargemaster, insurers pay negotiated rates, cash patients pay published cash prices, Medicare pays Medicare rates. The chargemaster is the starting point for inflated patient balances and a fiction in most cases.
CHIP, Children's Health Insurance Program. Federal-state program for children whose families earn too much for Medicaid but cannot afford private coverage. Appeals follow the Medicaid two-step pattern.
Coinsurance. The patient's percentage share of an allowed amount after the deductible (e.g., 20% coinsurance on $1,000 allowed = $200 patient share).
Copay. A fixed dollar amount the patient pays at the time of service (e.g., $30 copay for a primary-care visit).
CPT, Current Procedural Terminology. Five-digit codes maintained by the AMA describing medical procedures and services. Each code drives a price. The 99281-99285 series covers ED visits; the 99202-99215 series covers office visits.
CDT, Current Dental Terminology. Five-character codes maintained by the ADA describing dental procedures. Dental equivalent of CPT.
CMS, Centers for Medicare and Medicaid Services. The federal agency administering Medicare and overseeing Medicaid. Also enforces the Hospital Price Transparency Rule and the No Surprises Act.
CMS-20027. The form for a Level 1 Medicare Redetermination request. Optional; a written letter with the required elements is equally acceptable.
CMP, Civil Monetary Penalty. The federal government's preferred enforcement mechanism against non-compliant providers and plans. Hospital Price Transparency Rule CMPs run up to ~$2 million per year for large non-compliant hospitals.
Cost-sharing. Patient's total out-of-pocket responsibility under a health plan: deductible plus copay plus coinsurance. Capped annually by the plan's out-of-pocket maximum.
CRN, Civil Remedy Notice. Florida's first-party bad-faith mechanism under Fla. Stat. § 624.155. Filed electronically with the Florida DFS; gives the insurer 60 days to cure before the insured may sue.
Deductible. The amount a patient must pay out of pocket each year before the plan begins paying. High-deductible health plans have deductibles of $3,000 or more.
DOI, Department of Insurance. State-level regulator of insurance companies. Name varies: California has both DMHC (HMOs) and CDI (PPOs); Tennessee has TDCI; Georgia has OCI; Florida calls it OIR but routes complaints to DFS. Always state-level; not the federal CMS or DOL.
DPC, Direct Primary Care. A flat monthly-fee primary-care model outside insurance. Typically $50-$150/month for unlimited access. Doesn't cover specialists, hospital, or surgery.
DTPA, Deceptive Trade Practices Act. Texas's UDAP statute (Tex. Bus. & Com. Code § 17.41 et seq.). Among the most patient-favorable UDAP statutes in the country.
EHB, Essential Health Benefits. The federal-floor benefit categories that individual and small-group ACA plans must cover.
EBSA, Employee Benefits Security Administration. A DOL agency. Free informal intervention for ERISA-covered plan disputes at 1-866-444-3272. Underused; often resolves disputes that internal appeals cannot.
E/M, Evaluation and Management. The category of CPT codes used for office visits, ER visits, and inpatient encounters. The site of most upcoding disputes.
EOB, Explanation of Benefits. The insurance company's statement describing how a claim was processed: billed amount, allowed amount, plan payment, patient responsibility. Not a bill. Critical: never pay anything just because an EOB says "patient responsibility." Wait for the provider's actual bill and verify it matches.
EPSDT, Early and Periodic Screening, Diagnostic, and Treatment. A Medicaid benefit for under-21 enrollees entitling them to all medically necessary care to correct or ameliorate any condition, regardless of state-plan coverage limits. Strongest individual-benefit floor in US health law.
ERISA, Employee Retirement Income Security Act of 1974. Federal statute governing most employer-sponsored health plans. § 502(a) gives patients a private right of action to recover benefits. ERISA preempts most state insurance laws as applied to self-funded plans, which is critical for routing disputes correctly.
Extraordinary collection action, ECA. Per 26 CFR § 1.501(r)-6, includes lawsuits, wage garnishment, credit reporting, and denial of future care. Non-profit hospitals must complete eligibility determination for financial assistance before initiating any ECA.
FAP, Financial Assistance Policy. A non-profit hospital's written charity-care policy required under IRS § 501(r). Patient is entitled to a copy, a Plain Language Summary, and an application. Eligibility is typically pegged to a multiple of the federal poverty level (200-400%).
FBPA, Fair Business Practices Act. Georgia's UDAP statute (O.C.G.A. § 10-1-390 et seq.). Reaches original creditors, not just third-party collectors, broader than the federal FDCPA.
FCCPA, Florida Consumer Collection Practices Act. Florida's debt-collection statute. Reaches original creditors. Fla. Stat. § 559.55 et seq.
FCRA, Fair Credit Reporting Act. 15 U.S.C. § 1681 et seq. Governs credit-bureau reporting. Section 1681i creates the dispute-and-reinvestigate right; § 1681s-2 covers furnishers (the entities reporting the debt).
FDCPA, Fair Debt Collection Practices Act. 15 U.S.C. § 1692 et seq. Federal statute governing third-party debt collectors. Critical sections: § 1692g (30-day validation right), § 1692e (false representations), § 1692f (unfair practices). Does not reach original creditors.
FDUTPA, Florida Deceptive and Unfair Trade Practices Act. Florida's UDAP, but explicitly excludes regulated insurance practices. Use § 624.155 for insurer claims.
FFS, Fee-for-Service. A payment model where the provider is paid for each service. Distinguishes from capitation (flat monthly fee) and bundled payments. Most Medicare and traditional commercial insurance is FFS.
FPL, Federal Poverty Level. Annual income thresholds set by HHS. Used to calibrate financial-assistance eligibility (e.g., 200% FPL).
GFE, Good Faith Estimate. A pre-service cost estimate required under the No Surprises Act for uninsured and self-pay patients, delivered at least 1 business day before a scheduled service. Final bill more than $400 over the GFE triggers PPDR eligibility.
HCPCS, Healthcare Common Procedure Coding System. Codes used in addition to CPT for supplies, drugs, ambulance services, and certain procedures. Includes Level II (alphanumeric) codes like A0429 (BLS emergency ambulance) and J-codes for drugs.
HMO, Health Maintenance Organization. Plan type using a primary-care gatekeeper and a closed network. Knox-Keene Act regulates HMOs in California; similar state regulators elsewhere.
HPT, Hospital Price Transparency Rule. 45 CFR Part 180. Requires hospitals to publish a machine-readable file of standard charges and a consumer-friendly display. Compliance has been poor (34-36% per audits).
IDR, Independent Dispute Resolution. Federal NSA arbitration process. Two flavors: provider-payer IDR (between insurance company and provider, no patient involvement) and PPDR (between patient and provider).
IMR, Independent Medical Review. California's external-review mechanism for medical-necessity denials. Knox-Keene Act and CDI versions. ~73% favorable to enrollees per recent DMHC reports.
IRE, Independent Review Entity. Level 2 of Medicare Advantage and Part D appeals. Currently Maximus Federal Services.
IRO, Independent Review Organization. Generic term for the external-review reviewer used in ACA-compliant external reviews. State or accredited national IROs.
LCD / NCD, Local / National Coverage Determination. Medicare policies defining what is and isn't covered for specific conditions. Searchable at medicare.gov/coverage. Critical evidence in Medicare appeals.
MAC, Medicare Administrative Contractor. Regional contractor that processes Medicare Parts A and B claims. Names like Noridian, Palmetto, CGS. The first Medicare appeal level is to the MAC.
MBI, Medicare Beneficiary Identifier. The 11-character alphanumeric ID that replaced Social Security numbers on Medicare cards in 2018.
MCO, Managed Care Organization. A health plan contracted with a state Medicaid agency to administer benefits. Patient appeals go first to the MCO, then to the state fair hearing office.
MDM, Medical Decision Making. Component of E/M coding. Since 2021 (office) and 2023 (ED), MDM is one of the two factors driving the assigned level. The other is total time.
MRF, Machine-Readable File. The hospital's price file under 45 CFR § 180.50. Contains gross charges, payer-specific negotiated rates, cash prices, and de-identified min/max negotiated rates.
MSN, Medicare Summary Notice. Quarterly statement from Medicare to a beneficiary listing services billed and how they were processed. Functions like an EOB for Medicare.
NCCI, National Correct Coding Initiative. CMS-published code-pair edits identifying which CPT codes should not be billed together. Bundling violations show up here.
NCD, see LCD/NCD.
NCS, Non-Covered Services. State laws (e.g., Tenn. Code Ann. § 56-2-305) prohibiting dental and sometimes medical plans from controlling provider fees for services the plan does not cover.
NPI, National Provider Identifier. Ten-digit number identifying a specific health-care provider. Required on every claim. Patient can look up a provider's NPI at npiregistry.cms.hhs.gov.
NSA, No Surprises Act. Public Law 116-260, Division BB, Title I (Consolidated Appropriations Act, 2021). Effective January 1, 2022. Bans balance billing for emergency services, out-of-network ancillary at in-network facilities, and air ambulance. Does not cover ground ambulance.
OCI, Office of Commissioner of Insurance. Georgia's insurance regulator. Some states use this naming.
OMHA, Office of Medicare Hearings and Appeals. Federal office hosting ALJ hearings at Medicare appeal Level 3.
OOP, Out-of-Pocket maximum. The cap on cumulative cost-sharing in a benefit year. After hitting the OOP max, the plan pays 100% of allowed amounts for in-network services for the rest of the year.
OON, Out-of-Network. A provider that has no contract with the patient's health plan. Triggers higher cost-sharing and often balance billing (where not prohibited).
PPDR, Patient-Provider Dispute Resolution. Federal No Surprises Act mechanism for self-pay/uninsured patients whose final bill exceeds the GFE by $400+ from a single provider. Filed at nsa-idr.cms.gov. Collection-pause attaches during pendency.
PPO, Preferred Provider Organization. Plan type allowing out-of-network access at higher cost-sharing. Most commercial plans.
Presumptive eligibility. Under IRS § 501(r) and many state laws, enrollment in Medicaid, SNAP, WIC, or housing assistance can establish eligibility for hospital financial assistance without further income verification.
Prior authorization / Prior auth / PA. Insurance-side approval required before a service is rendered. Failure to obtain PA is a common denial reason; the patient is usually not responsible for the provider's failure to obtain it, though contesting this is friction-heavy.
QIC, Qualified Independent Contractor. Level 2 of the Original Medicare A/B appeal process. Independent of the MAC. Decisions usually within 60 days.
RVU, Relative Value Unit. The unit used to set Medicare fee-schedule prices. Each CPT code has assigned work, practice expense, and malpractice RVUs. Multiplied by a conversion factor and a geographic adjustment to produce the Medicare payment rate.
Reconsideration. Level 1 in Medicare Advantage; Level 2 in Original Medicare. Don't confuse with redetermination.
Redetermination. Level 1 in Original Medicare and Part D.
SDR, Selected Dispute Resolution. Entity certified by HHS to arbitrate IDR cases under the No Surprises Act, including PPDR.
SHIP, State Health Insurance Assistance Program. Free counseling for Medicare beneficiaries, including appeals help. Every state has one. Lookup at shiphelp.org.
SPD, Summary Plan Description. ERISA-required document summarizing a self-funded plan's terms. Contractually binding on the plan; the foundation of any ERISA appeal.
TIN, Tax Identification Number / EIN. Provider's federal tax ID. Useful for deduplication and identifying related providers under common ownership.
TPA, Third-Party Administrator. Company that processes claims for a self-funded employer plan. Common TPAs: Anthem, Cigna, UHC, Aetna, same names as fully-insured insurers, but operating as TPAs for self-funded plans.
UCC § 2-305, Uniform Commercial Code, Open Price Term. Provides that when a sales contract leaves the price open, the price must be a "reasonable price at the time for delivery" set "in good faith." Cited in medical-billing disputes to challenge inflated chargemaster prices.
UCR, Usual, Customary, and Reasonable. The traditional standard for out-of-network reimbursement. Largely supplanted by negotiated-rate methodologies but still appears in some plan documents.
UDAP, Unfair and Deceptive Acts and Practices. Generic term for state consumer-protection statutes. Texas DTPA, California CLRA, Georgia FBPA, Florida FDUTPA, Tennessee TCPA, New York GBL § 349 are all UDAP statutes.
VCC, Virtual Credit Card. Dental insurers' payment method that issues a single-use credit card number to providers instead of ACH or check, imposing processing fees on the provider. Prohibited as the sole reimbursement method in some states including Tennessee under § 56-2-305.
Write-off. The amount a provider deducts from its chargemaster when an in-network insurance contract requires it. Distinct from balance billing (which the provider tries to collect from the patient) and from charity-care write-off (which the provider voluntarily forgives).