The short answer: your denial letter is almost certainly quoting a statute back at you, and knowing which one tells you what to argue. California's medical-necessity test for mental health care has three parts — in accordance with generally accepted standards of care, clinically appropriate in type, frequency, extent, site and duration, and not primarily for the economic benefit of the plan or the convenience of the patient or provider.¹ Reviewers copy that language into denials nearly word for word. An appeal that answers those three clauses specifically is a different document from one that says the testing is important.
Read the denial for which clause it leans on
A real California denial, from the state's own published review records, reads: *"neither indication is present… As such, the requested ASD assessment/evaluation is not in accordance with the generally accepted standards of mental health and substance use disorder care, not clinically appropriate in terms of type, frequency, extent, site, and duration, and primarily for the convenience of the patient or provider."*²
That is the statute, recited. So the answer has to be evidence against those clauses: what the differential question is, why an interview cannot resolve it, which decision the results will change, and which professional-association guideline supports testing in this situation. "It would help us understand our son" is true and will lose.
Three denials California does not allow
1. "A school district could do this." Not permitted. A plan "shall not limit benefits or coverage for medically necessary services on the basis that those services should be or could be covered by a public entitlement program, including but not limited to, special education or an individualized education program, Medicaid, Medicare."³ One California insurer's own testing policy footnotes exactly this limit. Quote the section number in your appeal.
2. A blanket category exclusion. For California commercial DMHC and CDI plans, "categorical exclusion of benefits and coverage is prohibited" — a plan cannot rule out a whole class of service in the abstract; it has to decide your case.⁴
3. "Re-diagnose the autism first." Since 1 January 2026, a plan may not require someone already diagnosed with autism to be re-diagnosed to keep behavioural health treatment coverage, and may not "discontinue or delay existing treatment while waiting for a rediagnosis."⁵
The free review, and its real odds
If the internal appeal fails, California gives you an Independent Medical Review through the Department of Managed Health Care. It is free, and a doctor who does not work for your plan decides.
We counted the outcomes in the state's own published IMR dataset. Of the cases where psychological or neuropsychological testing itself was the service requested, 21 were upheld and 10 overturned — roughly a third reversed.⁶ That is worth knowing in both directions: it is not a formality, and it is not hopeless. A third of the people who were told no, and pushed, got the testing paid for.
Call the DMHC Help Center at 888-466-2219.
Do this, in order: get the denial in writing with the criteria named · ask the plan for the exact clinical criteria it applied and who wrote them, which it must provide at no cost⁵ · have the referring clinician write two paragraphs answering the three statutory clauses · file the internal appeal · then file the IMR. The full appeal walkthrough with the letter → · How to file with the DMHC →
Sources
- California Health & Safety Code §1374.72(a)(3)(A) — ca.gov.
- California Department of Managed Health Care Independent Medical Review determinations, published via the California Health and Human Services open data portal — quoted from an upheld 2026 determination — data.chhs.ca.gov.
- Health & Safety Code §1374.72(h). Some payer policies mis-cite this to §1374.721(h); the operative language is in §1374.72(h).
- Health Net / MHN California, position statement on authorisation of psychological and neuropsychological testing — the California notes on public-entitlement and categorical exclusions — healthnet.com.
- Health & Safety Code §1374.73(c), added by SB 402 (Stats. 2025, Ch. 413), effective 1 January 2026. Criteria must be made available at no cost under §1374.721.
- Counted by TherapyCalifornia from the DMHC IMR determinations dataset (42,749 records, 2001–2026, last modified 1 June 2026), restricted to determinations where psychological or neuropsychological testing was the requested service: 31 cases, 21 upheld, 10 overturned. Our count, from the state's data — data.chhs.ca.gov.
All figures checked 17 August 2026.