Original Medicare never concurrently reviews a PHP stay — it recertifies on day 18, then every 30 days

Original Medicare does not review a partial hospitalization stay while it is happening. No payer clinician calls on day three. The gate is a physician recertification due on the 18th day, then every 30 days after that.1 ecfr.gov

That is the exception. For nearly every other payer, the money on a residential, PHP or IOP episode is decided in concurrent review, several days at a time, while the patient is still in the building.

Three reviews, three different things at risk

MACPAC separates the tools cleanly: prior authorisation approves care before it is furnished, concurrent authorisation re-assesses the need “during the course of treatment,” and retrospective review denies payment “after it was delivered.”12 macpac.gov

The middle row is where behavioral health programs lose money. It is the only one where the clinical team is generating cost on the same day the decision is being made.

Medicare’s cadence is a physician’s obligation, not a payer’s

The Medicare fee-for-service outpatient prior authorization list holds eight service categories, from blepharoplasty to facet joint interventions, and not one of them is behavioral health.3 ecfr.gov PHP and IOP have never been on it.

Instead, 42 CFR 424.24 makes physician certification a condition of payment and fixes the recertification interval in regulation rather than plan policy.1 ecfr.gov

42 CFR 424.24(d)(3) and (e)(3); identical language at CMS Pub. 100-02 Ch. 6 §§ 70.3 and 70.4.1 ecfr.gov2 cms.gov

Three of those five rows are content requirements, and content is what fails. A recertification saying the patient is engaged and doing well satisfies nothing the regulation asks for. The hour thresholds those certifications attest to — 9 a week for IOP, 20 for PHP — are set out in our guide to the levels of care.

The recertification is not a progress note with a signature on it. It is a payment document that has to answer a question about the counterfactual — what happens if this stops.

What the reviewer is actually reading

CMS names four components used “to help determine whether the services provided were accurate and appropriate”: the initial certification, the physician recertification, the physician-signed treatment plan, and progress notes. Each note should describe the treatment service, the patient’s response, and how that response relates to the plan’s goals. Goals themselves must be “designed to measure the patient’s response to active treatment,” and activities that are primarily recreational and diversionary, or that only provide functional support without treating the presenting symptoms, are not PHP or IOP services at all.2 cms.gov

Commercial and MA reviewers work from proprietary instruments — MCG, InterQual, the ASAM Criteria, a plan’s own guidelines. The criteria differ. The evidence they run on does not: measurable goals, notes showing response against those goals, and a documented reason the next level down is not yet safe.

The clock on an extension request

Federal law does not say how often a plan may re-review. It says how fast the plan must answer once you ask.

The 24-hour rule is the one worth building a workflow around. An urgent request to extend an approved course of treatment must be decided within 24 hours — but only if it reaches the plan at least 24 hours before the authorised period runs out. Submit at hour 23 and the plan reverts to the ordinary urgent-claim clock of 72 hours.4 ecfr.gov

An adverse determination mid-stay is a different animal

For an ERISA plan, cutting an approved course short is not a neutral event. Any reduction or termination before the end of the approved period “shall constitute an adverse benefit determination,” and notice must come far enough in advance “to allow the claimant to appeal and obtain a determination on review of that adverse benefit determination before the benefit is reduced or terminated.”4 ecfr.gov Read literally, the appeal should conclude before the last authorised day.

Medicare Advantage carries a parallel trigger: written notice is required whenever a plan denies a service or “reduce[s] or prematurely discontinue[s] the level of care for a previously authorized ongoing course of treatment.”6 ecfr.gov

Medicaid managed care goes further. The notice must explain the right to continued benefits during the appeal, and the plan must continue them where the appeal is timely, involves termination or reduction of previously authorised services, the services were ordered by an authorised provider, and the original authorisation period has not expired.9 ecfr.gov10 ecfr.gov Note the fourth condition. Once the authorised period lapses, continuation is gone — which makes the filing date, not the clinical argument, the thing that preserves the days.

Who eats the days already delivered

It depends on the payer, and the answers point in opposite directions.

Medicare Advantage — the plan is locked in. Where an MA organisation approved care through prior authorisation, a pre-service determination, “or a concurrent determination made during the enrollee’s receipt of inpatient or outpatient services,” it “may not deny coverage later on the basis of lack of medical necessity” and may not reopen the decision absent good cause or reliable evidence of fraud or similar fault.5 ecfr.gov

Medicaid managed care — continued days are recoverable. If the appeal and any state fair hearing uphold the plan, it may recover the cost of services furnished while the appeal was pending, consistent with state recovery policy and its contract.10 ecfr.gov Win instead, and disputed services already furnished must be paid for, with anything not yet furnished authorised within 72 hours of the reversal notice.11 ecfr.gov

Commercial generally — approval is not payment. Prior authorisation approvals “are not binding, and usually contain language stating that the approval does not guarantee payment,” which preserves the payer’s ability to review retrospectively and deny.12 macpac.gov

Original Medicare — it turns on which statute the denial cites. Reasonable-and-necessary denials under §1862(a)(1)(A) are appealable by the provider and limitation on liability applies. Benefit category denials under §1861(ff) or §1835(a)(2)(F) — the day program that is really social or diversionary, the stable patient on medication management only — are not appealable by the provider, and limitation on liability does not apply.2 cms.gov Same unpaid days, no route.

The state layer moves the numbers again

State utilization review law overrides the federal floor for fully insured business, and it holds the tightest deadlines. New York requires a concurrent review determination within one business day of receipt of the necessary information, against three business days for a prospective review. For inpatient substance use disorder treatment the determination is due within 24 hours where the request is filed at least 24 hours before discharge — and while it is pending, the reviewer may not deny coverage on medical necessity or lack of prior authorisation grounds.13 nysenate.gov

New York’s Office of Mental Health also pushes plans off calendar-driven review, recommending trigger-based utilization review and stating it “shall not be conducted more frequently than is reasonably required” to assess medical necessity. For adult inpatient stays it advises applying concurrent review only from day 31 onward where no clinical trigger is met, and issuing no medical necessity denials for the first 30 days.14 omh.ny.gov

That is guidance in one state. No federal rule sets the re-review interval anywhere — it belongs to the plan and lives in the authorisation letter. The clock that starts when you submit, and the one that stops when the authorised period expires, belong to you.