Independent Medical Review (IMR) is how California resolves disputes about medical treatment — specifically, when the insurer's utilization review (UR) denies, delays, or modifies care your doctor requested.
How it fits together
Your treating doctor requests treatment → the insurer runs it through utilization review → if UR says no (or changes the request), you can challenge that decision through IMR. An independent physician, who doesn't know who you are, reviews your records against California's medical guidelines and issues a decision.
Deadlines are short
When you receive a UR denial, the paperwork includes an IMR application. You generally must submit it within 30 days of the denial. Missing that window can mean losing the right to challenge that particular treatment decision — so file promptly.
What IMR can and can't do
- IMR decides medical-necessity disputes — whether a specific treatment should be approved.
- It does not decide whether your injury is covered, your disability rating, or your benefits — those go through the QME/AME process and the WCAB.
- The reviewing doctor relies on the written record, so making sure your treating physician submits thorough documentation is important.
If IMR denies your treatment
IMR decisions are difficult to overturn — they can generally only be appealed on narrow grounds (such as fraud, bias, or a serious procedural error), not simply because you disagree. That's why it's worth making the strongest possible case the first time, with complete medical records and a clear treatment rationale from your doctor.