A defendant’s prior authorization of medical treatment does not bar it from submitting subsequent requests for the same treatment to utilization review (UR), according to a new published decision from the Second District Court of Appeal. Illinois Midwest Insurance Agency v. WCAB (Rodriguez), B344044, 11/10/25.
The appellate court rejected the Worker’s Compensation Appeals Board’s (WCAB) long-standing “Patterson Doctrine,” which had prevented defendants from submitting certain medical treatments to UR.
Per the Patterson doctrine, the WCAB retained jurisdiction to determine medical necessity, and if a defendant had previously authorized medical treatment, any termination of that treatment required proof of a change in the applicant’s medical condition. The defendant bore the burden of proving that the applicant’s condition had changed.
In Rodriguez, the defendant initially approved the applicant’s medical treatments, including home health care; however, it later denied the applicant’s physician’s request for renewed authorization of continued home health services. Relying on Patterson, the applicant bypassed the Independent Medical Review (IMR) process and instead challenged the denial before a workers’ compensation administrative law judge.
The appellate court concluded that the WCAB lacked jurisdiction to determine the medical necessity of home health care services in Rodriguez. The court explained that the 2013 statutory amendments, both in wording and intent, reassigned that authority from administrative law judges to medical reviewers through the IMR process. The court also noted that “irrespective of the reasons why a treating physician selects a particular duration of treatment in a request for authorization, the request is subject to utilization review if the employer objects, and timely submits to Independent medical review after that. Nothing in the statute prohibits an employer from seeking utilization review of subsequent requests for more of the same medical treatment.”
The 2013 amendments, including Labor Code section 4610.5(e), provide that “a utilization review decision may be reviewed or appealed only by independent medical review.” Importantly, section 4610.6(i) further emphasizes that “in no event shall a workers’ compensation administrative law judge, the appeals board, or any higher court make a determination of medical necessity contrary to the determination of the independent medical review organization.”
The justices further explained that extending Patterson to any form of ongoing medical care would effectively broaden it to encompass all treatment, a result that would conflict with the statutory UR and IMR framework established to resolve medical treatment disputes.
Rodriguez follows the statutory scheme originally envisioned by the legislature requiring defendants to review requests for authorization of treatment for ongoing care by UR without the added burden of proving a change in circumstances. Under Patterson, this proved difficult without additional discovery. Under Rodriguez any timely denial or modification of a request for authorization of treatment must be timely appealed to IMR not the WCAB. Defendants no longer need to litigate a “change of condition” before the WCAB under Patterson. For applicants, the prior strategy of bypassing IMR by invoking the Patterson doctrine—arguing that the treatment was “ongoing” because it had been previously authorized—fails. Though timely UR opinions and IMR appeals are still needed to avoid jurisdiction before the WCAB to resolve a medical dispute. This is not the final word on the issue as Rodriguez is likely to appeal the decision.
Patterson v. The Oaks Farm (2014) 79 CCC 910