COC (Formerly CPC-H) key terms

The diagnosis code set reported on outpatient claims, with codes up to seven characters describing conditions, symptoms, and external causes. Coders build codes from the Alphabetic Index and confirm them in the Tabular List using official guidelines.

The procedure code set used for inpatient hospital reporting. Outpatient facilities do not use it; candidates must recognize it and know that outpatient procedures are reported with CPT and HCPCS Level II instead.

A code set owned by the American Medical Association that describes medical, surgical, and diagnostic services. Outpatient facilities use it to report procedures and visits, and each code carries a defined descriptor and relative value.

A CMS-maintained code set beginning with a letter, covering supplies, drugs, durable medical equipment, and services not described in CPT. Facilities report items such as implants, injectables, and prosthetics with these codes.

A two-character code added to a CPT or HCPCS Level II code to supply extra detail, such as laterality, multiple procedures, or a distinct service. Correct modifier use supports accurate payment and prevents denials.

Appended to an evaluation and management code when a significant, separately identifiable E/M service is performed by the same provider on the same day as a procedure. The record must clearly support the separate service.

Modifier 59, or the more specific XE, XP, XS, and XU modifiers, which signals that two procedures were separate rather than one component of the other. It may override a coding edit only when documentation supports separate work.

A CPT or HCPCS code shown with a plus sign that is always reported with a primary procedure. Add-on codes describe extra work such as additional lesions, levels, or time and are never billed alone.

A single ICD-10-CM code that captures both an underlying condition and its manifestation, complication, or associated symptom. Using it avoids reporting two codes when one code fully describes the patient's condition.

An ICD-10-CM instruction meaning two conditions cannot be coded together because they are mutually exclusive. The coder selects the code matching the documented condition rather than reporting both.

The requirement to identify right, left, or bilateral when the code set offers those options. Missing or incorrect laterality is a common claim edit and denial reason in both diagnosis and procedure coding.

The diagnosis reported first on an outpatient claim, defined as the condition chiefly responsible for the services provided. It anchors medical necessity review and must be consistent with the procedure or reason for the visit.

A CPT category covering visits and consultations, such as clinic, office, and emergency department services. Level selection depends on the code set version, the applicable documentation guidelines, and whether facility or professional components are reported.

The E/M component reflecting the number and complexity of problems addressed, the amount of data reviewed, and the risk of complications. Current guidelines often allow the visit level to be selected on this component alone.

The bundle of services considered included with a surgical procedure, such as local anesthesia, the incision, and typical postoperative care. Understanding the package prevents unbundling and duplicate charges.

The number of times a code is reported on a claim, determined by time, quantity, or anatomic sites as defined in the code descriptor. Incorrect units cause overpayments, edits, or denials.

A two-digit code on the claim identifying where the service was furnished, such as a hospital outpatient department or an ambulatory surgery center. It influences payment rates and how the claim is processed.

A written communication from a coder to the treating provider requesting clarification or additional documentation when the record is ambiguous, incomplete, or conflicting. Queries must be non-leading and supported by clinical evidence in the record.

The determination that a service is reasonable and necessary for diagnosing or treating illness or injury. Payers deny claims when documentation fails to link the service to the patient's documented condition.

A form given to a Medicare beneficiary before a service likely to be denied as not medically necessary, transferring financial liability when the patient agrees to proceed. Proper use prevents avoidable provider write-offs.

An organized set of policies and controls, such as written standards, training, auditing, and a confidential reporting mechanism, that a facility uses to prevent and detect coding and billing violations.

The private insurer that processes Medicare claims for a region, issues local coverage determinations, and conducts audits. MAC guidance strongly shapes local coding and documentation expectations.

A planned review comparing coded records or claims with the supporting documentation to measure accuracy, target education, and identify overpayments before external reviewers do.

Time-based hospital services for patients who need monitoring while a decision is made about admission or discharge. Coding and payment depend on hours, status orders, and whether the service is packaged or separately payable.

Assignment of an emergency visit level by the hospital based on resources used, such as staff time, interventions, and complexity, rather than physician decision making. Facilities apply their own approved leveling guidelines.

A hospital-based site where outpatient services are furnished and billed under the hospital's provider number on an institutional claim, following outpatient prospective payment rules rather than physician office billing.

A clinic owned and operated by a hospital that meets CMS requirements to bill as part of the hospital, often resulting in a facility fee plus a separate professional fee.

Outpatient surgical care furnished in a hospital outpatient department or surgery center, with the patient discharged the same day. Coding requires accurate procedure codes, units, and diagnoses that support the surgery.

The rule requiring reduced payment when several endoscopic procedures are performed in one session, reported with the appropriate modifier and ranked by value. It prevents full payment for overlapping work.

The standard paper claim form used by institutional providers such as hospitals, containing fields for bill type, revenue codes, and discharge status. Knowing its layout helps coders catch data errors that cause rejections.

A four-digit number on the institutional claim that categorizes the type of service or accommodation charged, such as operating room, pharmacy, or supplies. Revenue codes group charges for billing and cost reporting.

The outpatient payment group to which each HCPCS code is assigned based on clinical similarity and resource cost. Codes grouped together receive the same payment rate under Medicare's outpatient system.

The Medicare system that pays hospital outpatient departments a fixed amount per payment group, applying packaging rules, status indicators, and beneficiary coinsurance calculations.

A letter assigned to each HCPCS code under the outpatient payment system indicating how it is paid, such as separately payable, packaged, or not paid. Status indicators explain why some services generate no separate payment.

CMS software that screens outpatient claims for errors such as invalid code combinations, age or sex conflicts, and incorrect units before payment. Its edits produce returns to the provider or claim denials.

The facility's internal list of services with descriptions and prices, mapped to CPT, HCPCS, and revenue codes. Accurate mapping is essential for correct claim submission, reimbursement, and regulatory reporting.

The payer's explanation of payment listing paid, adjusted, and denied claims with reason codes. Coders review it to spot error trends and correct the underlying causes.

A claim submitted with all required data accurate and complete so it can be processed without manual intervention or rejection. High clean claim rates shorten payment cycles and reduce rework.

The process of investigating why a payer rejected or reduced a claim, correcting the root cause, and resubmitting or appealing within payer deadlines. Trending denial reasons directs coding education and revenue improvement.