The California Department of Industrial Relations (DIR) and the Division of Workers’ Compensation (DWC) released their 2026 report on the state’s Independent Medical Review (IMR) program, which serves as the medical dispute resolution process for California’s workers’ comp system.

IMR trends offer valuable insight into how treatment decisions are being challenged and upheld in California’s workers’ comp systems and the report findings help support evidence-based care, anticipate regulatory shifts, and align with stakeholder needs.

In 2025, IMR activity increased, with 201,037 applications processed, an increase of 0.7% from 2024. After factoring out duplicate and ineligible applications, 152,351 IMR final determinations were made. Overall, 10.2% of treatment denials were overturned, a rate lower than 2024’s rate of 12.7%.

Pharmaceutical requests represented 30.6% of all treatment requests submitted for IMR, a modest decline from 32.7% in 2024. Opioids accounted for 21.5% of all pharmaceutical requests reviewed, followed by Topical Analgesics at 18.9%, and muscle relaxants at 15.8%.

Program services, behavioral and mental health services, and evaluations recorded the highest overturn rates. The Medical Treatment Utilization Schedule remained the primary resource used to determine medical necessity.