5.5 Denials, CDI, and Revenue Integrity

Clinical Documentation Integrity and the Query Process

Clinical Documentation Integrity (CDI) is the practice of ensuring the health record completely and accurately reflects the patient's clinical status so that coding, severity, and reimbursement are correct. CDI specialists review records concurrently (during the stay) and generate queries when documentation is conflicting, ambiguous, incomplete, or imprecise.

A compliant query follows AHIMA/ACDIS practice-brief rules. The query may not lead the provider toward a specific answer, and may never be driven solely by reimbursement.

Rules for a compliant query

• Be open-ended where possible; if multiple-choice, include clinically reasonable options and a "not clinically significant / unable to determine" choice.
• Be non-leading — never suggest a diagnosis the record does not support.
• Be supported by clinical indicators already in the record.
• Never indicate the financial impact of the answer.
• Be part of the permanent record per facility policy, and never ask the provider to add documentation only to raise the DRG.

Trap: A query that names the desired diagnosis and notes it "would increase payment" is non-compliant and leading — the classic wrong-answer scenario.

Denials Management and Appeals

A denial is a payer's refusal to pay all or part of a claim. Denials are grouped by cause:

Front-end denials are largely preventable by fixing registration and authorization. Clinical denials are fought with documentation and may require a physician advisor and a formal appeal. The Medicare appeals ladder has five levels: (1) redetermination by the MAC, (2) reconsideration by a Qualified Independent Contractor, (3) Administrative Law Judge hearing, (4) Medicare Appeals Council, (5) federal court.

Key metric: the denial rate (denied ÷ submitted) and the denial overturn rate measure both prevention and appeal effectiveness.

Audits, Case-Mix Index, POA, and Revenue Integrity

Audits verify that paid claims were correct. Recovery Audit Contractors (RACs) review Medicare claims after payment for both over- and underpayments and are paid on a contingency fee. Other reviewers include the Comprehensive Error Rate Testing (CERT) program, Medicare Administrative Contractors (MACs), and the OIG. HIM must respond to record requests within deadlines and track findings.

The case-mix index (CMI) is the average MS-DRG relative weight across a hospital's discharges. A rising CMI usually signals sicker patients and/or better documentation; a falling CMI can flag a documentation or coding problem.

Present-on-admission (POA) indicators (Y, N, U, W) report whether each diagnosis was present when the patient was admitted. POA drives the hospital-acquired condition (HAC) policy: a condition that is not POA and is on the HAC list will not increase the DRG payment, because Medicare will not pay extra for complications the hospital caused.

Revenue integrity is the umbrella discipline tying CDI, coding, charge capture, and compliance together so the organization captures all legitimately earned revenue — no more, no less.

POA indicator values

• Y — present on admission
• N — not present on admission
• U — documentation insufficient to determine
• W — clinically unable to determine

When and How to Query

CDI specialists query when the record shows a clinical indicator without a corresponding diagnosis, or carries conflicting documentation among providers. For example, lab values and treatment consistent with sepsis but no documented sepsis diagnosis would justify an open-ended query asking the provider to clarify the clinical significance. Queries may be concurrent (during the stay, the most effective) or retrospective (post-discharge, before billing). A verbal query is allowed but must be documented to preserve an audit trail.

The goal is always accuracy, not optimization: a compliant program is just as willing to query down (when documentation overstates severity) as up. That neutrality is what keeps the program defensible if a RAC or OIG auditor later reviews the queries.

Compliant vs. non-compliant query, side by side

Revenue Integrity as a Program

Revenue integrity is the organized effort to ensure that every service is documented, coded, charged, and billed accurately and compliantly — capturing all earned revenue while avoiding overpayment and fraud exposure. It connects four functions that historically operated in silos: charge capture, coding, CDI, and compliance.

A mature revenue-integrity program performs prebill DRG review, monitors the case-mix index for unexplained swings, audits high-risk DRGs and modifiers, tracks denial root causes back to their source department, and maintains the chargemaster. The payoff is fewer denials, audit-resistant claims, and a defensible compliance posture under the False Claims Act — which penalizes knowingly submitting false claims, the reason "upcoding" is both a revenue and a legal risk.

Two-midnight rule and level of care

Medicare's two-midnight rule guides whether a stay is properly inpatient versus observation (outpatient): stays expected to span at least two midnights generally qualify as inpatient. Misclassifying level of care is a top cause of clinical denials and RAC takebacks, so utilization review and physician advisors work this question concurrently — another place where documentation, not just clinical care, decides payment.