DME & HME glossary
Plain-English definitions of the durable and home medical equipment terms that actually affect getting paid — documentation requirements, billing codes, payment categories, and audit programs. Each entry adds the operational consequence, which is the part payer manuals leave out.
A
ABN — Advance Beneficiary Notice of Noncoverage
An ABN is a written notice a supplier gives a Medicare beneficiary before providing an item that Medicare is likely to deny, informing them they may be financially responsible. It must be issued before delivery, not afterward, and the beneficiary must choose an option and sign it.
Why it matters operationally: A missing or late ABN is one of the most common reasons a supplier cannot bill the patient after a denial. Automating the trigger — flagging at intake that an item is likely non-covered — is what prevents the write-off.
Assignment of Benefits — AOB
Assignment of benefits is the patient's authorization for the payer to pay the supplier directly rather than reimbursing the patient. Accepting assignment also means the supplier agrees to accept the allowed amount as payment in full for covered services.
Why it matters operationally: AOB is part of the intake document set. Incomplete intake paperwork is a leading cause of delayed billing, which is why intake validation is usually the highest-ROI workflow to automate first.
C
Capped Rental
Capped rental is a Medicare payment category in which certain DME items are rented for a fixed number of continuous months — generally 13 — after which ownership transfers to the beneficiary and rental payments stop. Standard wheelchairs, hospital beds, and nebulizers are typical capped rental items.
Why it matters operationally: Capped rental compliance is pure calendar tracking, and it is where suppliers quietly lose money in both directions: billing past the cap triggers recoupment, and dropping a month early forfeits revenue. It automates cleanly because the rules are date arithmetic.
CGM — Continuous Glucose Monitor
A CGM is a wearable device that measures interstitial glucose continuously and transmits readings to a receiver or smartphone. CGMs are billed as DME when supplied through a DME benefit, and coverage criteria vary by payer and by diabetes type and treatment regimen.
Why it matters operationally: CGM is a supply-driven category with recurring sensor and transmitter resupply, which makes eligibility-cadence automation directly revenue-relevant.
CMN — Certificate of Medical Necessity
A CMN was a CMS form documenting that an item was medically necessary, completed in part by the ordering physician. CMS eliminated CMNs and DIFs for claims with dates of service on or after January 1, 2023, consolidating documentation requirements into the Standard Written Order and the medical record.
Why it matters operationally: Legacy CMN references still appear in older internal SOPs and templates. If your intake checklist still asks for a CMN, it is out of date — the current requirement is an SWO plus supporting medical record documentation.
CMS — Centers for Medicare & Medicaid Services
CMS is the federal agency that administers Medicare and, with states, Medicaid. For DME suppliers, CMS sets coverage policy, the DMEPOS fee schedule, supplier standards, and the audit programs that govern reimbursement.
Why it matters operationally: CMS policy changes are the single largest external source of workflow churn in a DME operation, which argues for automation that is configurable rather than hard-coded to today's rules.
CPAP / BiPAP
CPAP (continuous positive airway pressure) and BiPAP (bilevel positive airway pressure) are devices that treat sleep apnea by delivering pressurized air. CPAP delivers one constant pressure; BiPAP delivers a higher pressure on inhalation and a lower one on exhalation.
Why it matters operationally: PAP is the archetypal resupply category — masks, cushions, tubing, and filters all have replacement schedules. Most suppliers reach only a fraction of their eligible PAP panel manually, which is where automated outreach recovers the most revenue.
D
Denial
A denial is a payer's refusal to pay a submitted claim. Denials are typically categorized as technical (missing or invalid documentation, coding, eligibility, or timely filing) or medical necessity (the payer disagrees the item was warranted).
Why it matters operationally: The distinction matters operationally: technical denials are largely preventable by validating documentation before submission, while medical-necessity denials require clinical appeal. Pre-claim validation targets the preventable category.
DME — Durable Medical Equipment
DME is equipment that can withstand repeated use, is primarily used for a medical purpose, is generally not useful in the absence of illness or injury, and is appropriate for use in the home. All four criteria must be met for Medicare DME coverage.
Why it matters operationally: The four-part definition is why coverage disputes so often turn on documentation of the home-use and medical-purpose criteria rather than on the device itself.
DMEPOS — Durable Medical Equipment, Prosthetics, Orthotics, and Supplies
DMEPOS is the CMS category covering durable medical equipment, prosthetics, orthotics, and supplies. It is the umbrella term used in Medicare fee schedules, supplier standards, accreditation requirements, and competitive bidding programs.
Why it matters operationally: When searching CMS policy, DMEPOS is usually the correct search term — policy documents rarely use “DME” alone.
E
EDI 270 / 271
The 270 is the HIPAA-standard electronic eligibility and benefit inquiry a provider sends to a payer; the 271 is the payer's response describing coverage, benefits, and limitations.
Why it matters operationally: Automated 270/271 checks at intake catch coverage problems before delivery rather than after billing, which is the difference between a rescheduled delivery and an unrecoverable write-off.
EDI 276 / 277
The 276 is the HIPAA-standard electronic claim status inquiry; the 277 is the payer's response reporting where the claim stands in adjudication.
Why it matters operationally: Polling 276/277 on a schedule replaces the staff habit of manually checking payer portals, and it surfaces stalled claims while there is still time to act on them.
EDI 835
The 835 is the HIPAA-standard electronic remittance advice a payer returns to explain how a claim was adjudicated, including payments, adjustments, and denial reason codes.
Why it matters operationally: The 835 is the richest available source of denial-pattern data. Parsing reason codes across thousands of claims reveals which documentation gaps are actually costing money — and that analysis is what tells you which workflow to automate first.
EDI 837
The 837 is the HIPAA-standard electronic healthcare claim transaction used to submit claims to payers. The 837P (professional) and 837I (institutional) variants cover different provider types; DME claims are typically submitted as 837P.
Why it matters operationally: Because the 837 is a structured format, most claim rejections are detectable programmatically before submission — which is exactly what a billing pre-flight check does.
F
Face-to-Face Encounter — F2F
A face-to-face encounter is a documented in-person or, where permitted, telehealth visit between the treating practitioner and the beneficiary, required for certain DMEPOS items. The encounter must be related to the condition supporting the need for the item and must occur within a required timeframe relative to the order.
Why it matters operationally: Missing or out-of-window F2F documentation is a frequent audit finding. Because the requirement is date-bounded, it validates well automatically at intake.
H
HCPCS — Healthcare Common Procedure Coding System
HCPCS is the coding system used to bill Medicare and most other payers. Level I is CPT; Level II codes, which cover DMEPOS items and supplies, are the alphanumeric codes DME suppliers use daily.
Why it matters operationally: Correct HCPCS selection drives both reimbursement rate and coverage criteria, so miscoding surfaces as a denial rather than as an obvious error.
HME — Home Medical Equipment
HME is medical equipment supplied for use in the home. In practice HME and DME are used interchangeably; HME is more common in industry and trade-association usage, while DME is the formal Medicare benefit term.
Why it matters operationally: Worth knowing for search and vendor research — the same concept is indexed under both terms, and some resources appear under only one.
K
KX Modifier
The KX modifier is appended to a claim line to attest that the coverage criteria in the applicable policy have been met and that the required documentation is on file with the supplier.
Why it matters operationally: KX is an attestation, not a shortcut — applying it without the underlying documentation is exactly what audits look for. Automating the check that documentation genuinely exists before KX is applied is a meaningful compliance control.
L
LCD — Local Coverage Determination
An LCD is a coverage policy issued by a Medicare Administrative Contractor specifying when an item is considered reasonable and necessary within that contractor's jurisdiction. LCDs are typically paired with Local Coverage Articles containing the detailed documentation and coding requirements.
Why it matters operationally: LCDs are the operative rulebook for most DME coverage questions, and because they are jurisdiction-specific, multi-state suppliers cannot assume one set of criteria applies everywhere.
Length of Need
Length of need is the period the ordering practitioner expects the beneficiary to require the item, documented on the order. It may be a specific duration or indicate a lifetime need.
Why it matters operationally: Length of need drives re-authorization and renewal timing, making it a natural trigger field for automated re-order and re-auth workflows.
M
MAC — Medicare Administrative Contractor
A MAC is a private contractor that processes Medicare claims for a defined jurisdiction. DMEPOS claims are handled by DME MACs, which also publish the LCDs and coverage articles governing their region.
Why it matters operationally: Which DME MAC applies depends on the beneficiary's permanent address, not the supplier's location — a routing rule worth encoding rather than leaving to staff memory.
Medical Necessity
Medical necessity means an item is reasonable and necessary for the diagnosis or treatment of an illness or injury, or to improve the functioning of a malformed body member. It is established by documentation in the medical record, not by the supplier's own paperwork.
Why it matters operationally: This is the most common point of confusion in DME billing: a complete supplier file does not establish medical necessity if the practitioner's chart notes do not support it.
N
NPI — National Provider Identifier
The NPI is a unique 10-digit identifier assigned to healthcare providers and used on all HIPAA standard transactions. Ordering practitioners must have a valid NPI and be eligible to order DMEPOS for claims to pay.
Why it matters operationally: Validating the ordering practitioner's NPI and DMEPOS ordering eligibility at intake prevents a denial category that is entirely avoidable and frequently missed.
P
PAP Compliance
PAP compliance refers to documented adherence to positive airway pressure therapy, typically measured by device-reported usage over a defined period during an initial trial. Medicare requires documented adherence plus a clinical re-evaluation to continue coverage beyond the trial period; specific thresholds and timeframes are set by policy and vary by payer.
Why it matters operationally: Compliance data arrives from device manufacturer portals rather than the DME platform, which is why PAP compliance tracking usually requires connectors to systems like AirView or Care Orchestrator and is a natural automation target.
PDAC — Pricing, Data Analysis and Coding contractor
PDAC is the CMS contractor that determines correct HCPCS coding for DMEPOS products and maintains the Product Classification List showing which specific products are verified under which codes.
Why it matters operationally: Checking a product against the PDAC list before billing resolves most coding disputes in advance. It is a lookup, which means it automates.
POD — Proof of Delivery
Proof of delivery is documentation that the beneficiary received the item, including the beneficiary's name, delivery address, item description and quantity, delivery date, and a signature. Suppliers must retain POD and produce it on audit.
Why it matters operationally: Missing POD is one of the most common causes of a claim becoming unbillable, and it is entirely preventable. Automated POD chasing before billing is among the highest-return workflows in a DME operation.
Prior Authorization — PA
Prior authorization is a payer requirement to approve an item before it is provided. Medicare operates required prior authorization for certain DMEPOS items on its Master List, and many commercial payers apply broader PA requirements.
Why it matters operationally: Prior auth is the workflow most often cited as a bottleneck, but the expensive failure is rarely the submission — it is the follow-up. Auths that expire unworked or lapse before delivery are silent revenue loss, which is why tracking matters more than submitting.
R
RAC — Recovery Audit Contractor
RACs are contractors that review Medicare claims after payment to identify and recover improper payments. RAC reviews can be automated (data-driven) or complex (requiring medical record review).
Why it matters operationally: RAC exposure is retrospective, so the defense is documentation that was correct at the time of billing. This is the strongest argument for validating documentation before submission rather than reconstructing it years later under audit.
Recoupment
Recoupment is a payer's recovery of a previously paid amount, typically after an audit determines the claim should not have been paid. Recovery is often taken by offsetting future payments rather than by direct invoice.
Why it matters operationally: Because recoupment offsets future remittances, a large audit finding shows up as unexplained cash flow disruption — often noticed in the bank account before it is understood in billing.
Resupply
Resupply is the recurring provision of consumable items associated with a device — PAP masks, cushions, tubing, and filters; CGM sensors and transmitters; ostomy and urological supplies. Payers set replacement frequency schedules governing how often each item is covered.
Why it matters operationally: Resupply is the most automation-responsive revenue stream in DME because eligibility is a calculable date and outreach is repetitive. Manual programs typically reach only part of the eligible panel simply because the work scales with headcount.
S
Same or Similar
Same or similar refers to a check on whether a beneficiary already has equipment that serves the same purpose, since Medicare generally will not pay for duplicate equipment within its reasonable useful lifetime.
Why it matters operationally: Same-or-similar denials are especially costly because the equipment has already been delivered before the problem surfaces. Checking eligibility history at intake rather than at billing is the fix.
SWO — Standard Written Order
The SWO is the current CMS order requirement for DMEPOS, replacing the older CMN and DWO forms. It must include the beneficiary's name or identifier, the order date, a description of the item, the quantity if applicable, and the treating practitioner's name or NPI and signature.
Why it matters operationally: The SWO's required elements are a fixed, checkable list — which makes it one of the cleanest documentation validations to automate at intake.
T
TPE — Targeted Probe and Educate
TPE is a Medicare medical review program in which a MAC reviews a small sample of a supplier's claims, provides education on errors found, and repeats the cycle. Suppliers who continue to show high error rates across rounds may be referred for further action.
Why it matters operationally: TPE is targeted at suppliers with unusual billing patterns, so the practical defense is consistent documentation rather than reacting once a probe letter arrives.
W
WOPD — Written Order Prior to Delivery
WOPD is the requirement that, for certain DMEPOS items, the supplier must have a complete written order in hand before delivering the item. Delivering first and obtaining the order afterward makes the claim non-payable.
Why it matters operationally: WOPD is a hard sequencing rule, which makes it well suited to an automated gate that blocks scheduling until the order is on file — preventing a loss that cannot be corrected after the fact.
Which of these is costing you the most?
A free workflow audit quantifies where documentation gaps, unworked resupply, and stalled authorizations actually cost you — in hours and dollars. You keep the numbers either way.