What California's own data shows.
When a mental-health or substance-use denial reaches California's Independent Medical Review, an independent panel decides whether the plan was right. The state publishes every determination. Here is what that public record shows.
of mental-health IMRs decided in 2025 went in the patient's favor: 309 of 389 decisions, in the state's own data.
Mental-health categories only (mental disorder, autism spectrum, and mental/behavioral/neurological), 2025 determinations. This is a historical aggregate, not a prediction for any individual case.
59% across all years on record (2002–present): across all 7,571 behavioral-health IMR determinations. That includes every case with a mental-health, autism-spectrum, or mental/behavioral/neurological diagnosis, whatever service was denied. 4,435 were overturned and 3,136 upheld, so 59% went the patient's way. Recent years run well above the all-time average: SB 855, California's strengthened parity law, took effect in 2021, and 2025 is the strongest year on record. Same CalHHS DMHC IMR dataset as below (the “By treatment” section further down slices the same cases by the denied service instead of the diagnosis).
By type of denial.
By year.
Since SB 855 took effect in 2021, every complete year shown has run above the pre-2021 average. The rates vary from year to year.
2026 shown after the year completes.
These counts include only published cases that reached a determination. They do not count matters resolved before a published IMR decision, and they do not estimate the probability of coverage in any individual case.
By treatment.
All behavioral-health years in the file (2002–present), the same cases as above but grouped by the denied service instead of the patient's diagnosis: every service category inside the behavioral-health IMR dataset with at least 20 determinations (the diagnosis was behavioral; the denied service sometimes ranged wider, including pharmacy, equipment and procedures), highest overturn rate first. Because this cut is by service, the “Mental Health” row here (n=4,788) is narrower than the 7,571 determinations above. The two happening to round to the same 59% is a coincidence, not one figure disagreeing with itself.
How long a review takes.
Five regulators, one of them is yours.
- DMHC ↗Most California plans: HMOs and most employer PPOs. Runs the IMR process in this data.
- CDI ↗Some individual and PPO insurance policies sold as insurance rather than a health plan.
- DHCS ↗Medi-Cal, with its own state fair-hearing and appeal process.
- EBSA / Dept. of Labor ↗Self-funded employer (ERISA) plans; external review runs through a federal process.
- Medicare ↗Federal program with its own federal appeal ladder.
You don't have to figure out which one applies: Path Finder selects a likely route from your answers →
Where these numbers come from.
Source: CalHHS Open Data Portal, DMHC Independent Medical Review Determinations (2001–present). We downloaded the full public dataset (42,749 determinations across all conditions) and filtered to the behavioral-health diagnosis categories: Mental Disorder, Autism Spectrum, Mental Behav Neur (7,571 determinations). Overturn rate is the share of those cases decided "Overturned Decision of Health Plan" out of all overturned-or-upheld determinations.
An important honest caveat: these are historical aggregates. Outcomes vary case by case, and a past overturn rate is not a prediction or a guarantee for any individual appeal. The dataset contains no insurer or health-plan field, so no plan-specific figures can be derived from it, and none are shown here.
Published 2026-06-01. Downloaded July 2, 2026; verified weekly.
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