California external-review reversal rate

72.7%

Reported for 2024 · State-reported

Administered by California Department of Managed Health Care (DMHC). This is one cell of a 50-state public-record dataset; across measured jurisdictions the reported rate ranges from 17.0% (West Virginia) to 80.0% (Connecticut).

Read this number carefully

Headline: ~73% of IMR cases end with enrollee receiving requested service (full+partial overturn by IMRO + plan reversals during review). Of cases reaching final IMRO determination, overturn rate of treatment-denial decisions was 12.7% in 2024 (up from 10.2% in 2023). Full open-data trend file: https://data.chhs.ca.gov/dataset/independent-medical-review-imr-determinations-trend

Denominators are not comparable between jurisdictions. Some states count cases received, some completed, some completed-and-eligible; some publish a complaint-process reversal rate broader than IRO-only external review. We reproduce the figure exactly as the jurisdiction published it and do not extrapolate.

Official sources

California IMR determinations trend — CHHS open data

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Apellica (2026). The Apellica External Review Index — California. v1.0. Released 2026-05-19; resource updated 2026-09-04. CC-BY-4.0. https://apellica.com/external-review-index/california

Spot an error in this figure or its source? Email editorial@apellica.com with the jurisdiction, the value you believe is correct, and a public-record URL. Apellica is an independent appeal-preparation service — not a regulator, law firm, or insurer — publishing this public regulatory data as a free research resource.