Most injured workers have never heard of Independent Medical Review — and the insurance company is counting on that. IMR is the process that can override a Utilization Review denial and force your insurer to approve the treatment your doctor says you need. But if you miss the deadline, that option is gone forever.

Let’s break it down in plain English.

 

First — What Is UR (Utilization Review)?

When your treating physician requests medical treatment — surgery, physical therapy, medication, an MRI, a specialist referral — the insurance company doesn’t just approve it. They run it through a process called Utilization Review, or UR.

A UR reviewer — often a doctor who has never met you and may not even be licensed in California — compares your treating physician’s request against a set of medical guidelines called the Medical Treatment Utilization Schedule (MTUS). If they decide it doesn’t meet those standards, they issue a denial.

Your treating doctor said yes. A stranger on the phone said no. And now you can’t get the care you need.

This is where IMR comes in.

 

What Is IMR — and How Does It Work?

Independent Medical Review is a process established by California Labor Code §4610.5. When a UR denial is issued, you have the right to request an IMR — an independent review by a medical professional with no financial stake in the outcome.

⚖️  IMR Process Step by Step 1. Your treating doctor submits a treatment request. 2. The insurance company’s UR reviewer denies or modifies it. 3. You (or your attorney) request IMR within 30 days of the UR denial. 4. MAXIMUS Federal Services (the state’s IMR organization) assigns a qualified reviewer. 5. The reviewer examines all submitted medical records and issues a determination. 6. If the IMR reviewer overturns the denial, the insurer MUST authorize the treatment. 7. If the IMR upholds the denial, the decision is binding — with very limited appeal rights.

 

The 30-Day Deadline — This Cannot Be Overstated

⏰  DEADLINE ALERT: You have 30 days from the date of the UR denial to request IMR. If you miss this deadline, you lose your right to challenge the denial through IMR. This is not a soft deadline. There is no extension for forgetting. Don’t let the clock run out on your right to treatment.

 

The 30-day window begins when the UR denial is issued — not when you receive it, not when you understand it. This is why having an attorney tracking your case matters. We watch the calendar so you don’t lose your rights to a missed deadline.

 

What Happens After IMR?

If the IMR reviewer sides with your doctor, the insurer must authorize and provide the treatment. End of story. They cannot appeal that decision. Under California law, an IMR determination in your favor is binding on the insurance company.

If the IMR reviewer upholds the denial, the decision is also binding — but there are narrow grounds to appeal to the WCAB. Under LC §4610.6, the WCAB can review an IMR determination only if there was fraud, conflict of interest, or plainly erroneous factual findings. These are high bars, but they’re not impossible.

⚖️  Legal Anchor: California Labor Code §4610.5 and §4610.6 §4610.5 establishes your right to IMR when UR denies or modifies a treatment request. §4610.6 governs when a WCAB appeal of an IMR determination is permitted. The grounds are narrow: fraud, conflict of interest, or plainly erroneous factual findings. Most denials survive IMR review without a viable WCAB appeal — which is exactly why getting it right at the IMR stage matters enormously.

 

Why Your IMR Request Must Be Done Right the First Time

IMR is not just a form you fill out. The reviewer looks at the medical documentation that’s been submitted — your treating doctor’s request, the clinical notes, the diagnostic findings. If the medical record isn’t strong going in, the IMR reviewer may not have what they need to overturn the denial.

An experienced workers’ comp attorney can help make sure your treating physician has submitted all of the supporting documentation, that the request is framed within the MTUS standards, and that the deadline is met without question.

We have seen IMR overturns on surgeries, medication approvals, physical therapy authorizations, and specialist referrals. It works — when it’s done correctly and on time.

 

If your treatment has been denied through UR, don’t wait. Call us. The clock is running.