1. DWC

Independent Medical Review (IMR)

What is IMR

California's workers' compensation system uses a process called independent medical review (IMR) to resolve disputes about the medical treatment of injured employees. As of July 1, 2013, medical treatment disputes for all dates of injury will be resolved by physicians through an efficient process known as IMR, rather than through the often cumbersome and costly court system.

A request for medical treatment in the workers' compensations system must go through a "utilization review" process to confirm that it is medically necessary before it is approved. If utilization review denies, delays or modifies a treating physician's request for medical treatment because the treatment is not medically necessary, the injured employee can ask for a review of that decision through IMR.

The costs of IMR are paid by employers who are required by law to provide injured employees with all medical treatment that is reasonable and necessary to cure or relieve the effects of a work-related injury. The DWC is required to contract with one or more independent medical review organizations (IMROs) to conduct IMR on its behalf.

The costs of IMR are based upon the nature of the medical treatment dispute and the number of medical professionals needed to resolve the dispute, and are significantly lower than the cost to resolve a dispute through litigation.

Keys to a successful IMR

It is the claims administrator's responsibility to:

• Send the injured worker a copy of the utilization review (UR) decision letter on a request for treatment, and, if applicable, the supporting recommendation by a utilization review organization.
• Send the completed IMR application form (DWC IMR-1 form) to the injured worker if the UR decision denies or modifies the request for treatment. If the injured worker is represented, please additionally include the Authorized Representative Designation form.
• Make sure the IMR application form is the correct DWC IMR-1 form (not MPN-IMR form, not a modified or self-created form).
• Clearly indicate type of review on the application based on checkboxes at the top of page 1 of the application. Expedited reviews must be accompanied by a physician statement of necessity or the UR must have been conducted in an expedited manner.
• Include the WCIS number (also known as the JCN).
• Indicate whether liability is being disputed on the application. If liability is disputed, IMR is not available until the liability issue has been resolved. For claims that are under investigation and for which liability has not yet been denied, IMR is available within the first 90 days after the claim is presented, for medical treatment costs up to $10,000.

If you are an injured worker or the designee, to submit a request for IMR, it is very important do the following:

• Include a copy of the complete utilization review (UR) determination with the IMR application form that was provided to you by your claims adjustor.
• Sign the IMR application form before submitting a request for IMR.
• If you would like to designate a representative for the IMR application, please fill out an Authorized Designated Representative form.
• Send the signed IMR application, the UR determination, and, if applicable, the signed Authorized Designated Representative form to the address on the form within the time frame as indicated (either 10 or 30 days of the UR determination letter) in the IMR application under the section titled, "Deadline for Filing IMR Application.

As of July 1, 2013, all dates of injury are eligible for IMR.

If you did not receive or have misplaced the IMR application form, you may contact the claims administrator for another copy.

For questions regarding your IMR request, please contact your employer's insurance company claims administrator.

What happens after the Administrative Director determines the dispute is eligible for IMR?

• Within one business day of the Administrative Director's finding that a dispute is eligible for IMR, Maximus will send the parties a Notice of Assignment and Request for Information (NOARFI), which informs the parties that the dispute has been assigned for review and what kind of review will take place.
• For a regular review:
  • The required medical records must be provided to Maximus within 15 calendar days of the date designated on the mailed notification or within 12 calendar days of an electronic notification.
• For a review of a drug on the MTUS Drug Formulary:
  • The required medical records must be provided within 10 days.
• For an expedited review:
  • The required medical records must be provided to Maximus within 24 hours following receipt of the notification.
• The claims administrator must also send the employee or the employee’s representative a notification that lists all of the documents submitted to Maximus and a copy of all of the documents that were not previously provided to the employee or the employee’s representative.
• The best and most reliable way to transmit medical records to Maximus is via MOVEit.  MOVEit is a web-based portal that allows you to submit files to MAXIMUS securely and electronically. MOVEit provides much better traceability than paper and fax.
• If you wish to use MOVEit or have questions about it, please feel free to contact MAXIMUS by email at IMRhelp@maximus.com or by phone at 1-855-865-8873.

April 2026