What Is Utilization Review?

Utilization review (UR) is the process health insurance companies use to evaluate whether medical care is appropriate, necessary, and cost-effective before they agree to pay for it. UR is not a single event — it happens at three points in your care: before treatment (prospective), during ongoing treatment (concurrent), and after treatment is completed (retrospective). Understanding how UR works at each stage is essential for protecting your access to care and your right to appeal.

The Three Types of Utilization Review

Prospective Review (Prior Authorization Denied: How to Appeal" class="auto-link">Prior Authorization) Prospective UR happens before you receive care. It is what most people know as "prior authorization" — your doctor requests approval for a treatment, and a UR reviewer decides whether it meets medical necessity criteria before the service is rendered. This is the most common UR encounter for patients.

Prospective UR decisions must be made within defined timeframes: typically 15 days for standard requests and 72 hours for urgent requests (24 hours under some state laws and the 2024 CMS rule for Medicare Advantage plans).

Concurrent Review (Continued Stay Review) Concurrent UR happens while you are receiving ongoing treatment — most commonly during an inpatient hospitalization. The insurer's reviewer evaluates whether continued hospitalization (or continued treatment in any setting) is still medically necessary. If the reviewer determines you no longer meet inpatient criteria, they issue a "notice of non-certification" — effectively telling the hospital that coverage will end on a specific date.

Concurrent review denials can be extremely disruptive, because they happen while you are still in the hospital. You and your doctor may believe continued stay is necessary while the insurer disagrees. You have the right to request an expedited appeal before discharge.

Retrospective Review (Post-Service Denial) Retrospective UR happens after you have already received care. The insurer reviews the claim and determines that the service was not medically necessary after the fact — resulting in a denial you receive weeks or months later. Retrospective denials are particularly frustrating because you had the procedure in good faith and now face an unexpected bill.

Retrospective denials are fully appealable, and courts and regulators have increasingly scrutinized retrospective UR as unfair — especially when prior authorization was not required.

Who Actually Does Utilization Review

Most large insurers do not perform all UR in-house. They outsource to specialized third-party utilization management companies. Knowing who is reviewing your claim matters because it tells you who to contact and what criteria they use.

eviCore healthcare: One of the largest UR vendors, handling imaging (MRI, CT, PET), musculoskeletal procedures, cardiology, oncology, and specialty drugs for many major insurers including UnitedHealthcare, Cigna, Aetna, and Blue Cross plans.

AIM Specialty Health (Cigna): Handles specialty care UR for Cigna-affiliated plans.

Magellan Health (Magellan Rx Management): Specialty pharmacy and behavioral health UR.

Carelon (Anthem/Elevance subsidiary): Behavioral health, musculoskeletal, and radiology UR.

InterQual and MCG (Milliman): These are not UR vendors but UR criteria products — proprietary clinical decision tools that UR companies use. Many UR denials cite "InterQual criteria not met" or "MCG guidelines not met" without disclosing the actual criteria. You have the right to request these criteria.

How to Challenge a Utilization Review Denial

Step 1: Get the specific criteria Ask your insurer (or the UR vendor) for the exact criteria that were used and which specific criterion was not met. This is your roadmap for the appeal. Without it, you are appealing blindly.

Step 2: Request a peer-to-peer review Your treating physician can speak directly with the UR reviewer (or a physician reviewer). Peer-to-peer reviews have among the highest overturn rates of any appeal mechanism. They must be requested quickly — usually within a few days of the denial. Your doctor should call proactively rather than waiting.

Step 3: File a formal internal appeal Submit a written appeal with your doctor's letter of medical necessity, clinical literature supporting the treatment, and documentation that directly addresses the unmet criteria. Make the case specific, not general.

Step 4: For concurrent review denials, request expedited appeal If you are still in the hospital or receiving ongoing treatment, you can request an expedited internal appeal. The insurer must respond within 72 hours (or 24 hours for truly urgent cases). Your doctor should be involved in preparing this immediately.

Step 5: File for External Independent Review: Complete Guide" class="auto-link">external review After exhausting internal appeals, request independent external review. External reviewers are not affiliated with your insurer and apply objective clinical standards. Roughly 40% of UR-related denials that reach external review are overturned.

Step 6: File a complaint with regulators For fully-insured plans, your state insurance commissioner can investigate UR decisions that appear to violate state law or medical necessity standards. ERISA plans fall under federal jurisdiction (Department of Labor).

What to Do If This Applies to You

If your care has been denied through utilization review, move quickly. UR appeals have strict deadlines, and concurrent review denials must be challenged before or at discharge to preserve your rights. Contact your doctor's office immediately, ask them to request a peer-to-peer review, and begin gathering the clinical documentation for a formal appeal.

Fight Back With ClaimBack

Utilization review denials are designed to be difficult to challenge — but they are not impossible to overturn. ClaimBack helps you understand the specific UR criteria your insurer applied, build a targeted appeal that addresses each unmet criterion, and move through the process at the speed your situation demands.

Your treatment decisions belong to you and your doctor. When a UR reviewer interferes, ClaimBack gives you the tools to fight back effectively.

Start My Free Appeal →

Related Reading

• How to Write an Insurance Appeal Letter
• What Is Medical Necessity?
• Common Reasons Insurance Claims Are Denied