F28
BillableOther psychotic disorder not due to a substance or known physiological condition
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F28 an HCC code?
Yes. F28 maps to Delusional and Other Specified Psychotic Disorders under the CMS-HCC V28 risk adjustment model (and Reactive and Unspecified Psychosis under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for F28
For F28to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed F28 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F28 is the ICD-10-CM diagnosis code for other psychotic disorder not due to a substance or known physiological condition. A psychotic disorder where a person experiences hallucinations, delusions, or disorganized thinking that is not caused by substance use, medication, or a medical condition. F28 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders (f20-f29).
Under the CMS-HCC V28 risk adjustment model, F28 maps to Delusional and Other Specified Psychotic Disorders (HCC 152) with a community, non-dual, aged base RAF weight of 0.546. Under the older CMS-HCC V24 model, F28 maps to Reactive and Unspecified Psychosis (HCC 58) with a community, non-dual, aged base RAF weight of 0.508. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Ensure documentation rules out substance use, medication effects, and medical causes before coding. Because F28 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F28 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Ensure documentation rules out substance use, medication effects, and medical causes before coding
- •This is a diagnosis of exclusion; document the workup performed to eliminate other causes
Clinical Significance
Other psychotic disorder not due to a substance or known physiological condition is a diagnosis of exclusion for psychotic presentations that do not fit standard categories (schizophrenia, delusional disorder, brief psychotic disorder, schizoaffective disorder). This may include chronic hallucinatory psychosis or other atypical psychotic presentations. It requires thorough clinical evaluation to exclude substance-induced and medical causes of psychosis. Accurate coding ensures these complex patients receive appropriate risk adjustment.
Documentation Requirements
- ✓Documentation of psychotic symptoms (hallucinations, delusions, disorganized thinking)
- ✓Assessment by a qualified mental health professional
- ✓Documentation ruling out substance-induced psychosis (drug screening, history)
- ✓Documentation ruling out psychosis due to medical conditions (metabolic, neurological, infectious workup)
- ✓Explanation of why the presentation does not fit schizophrenia, delusional disorder, brief psychotic disorder, or schizoaffective disorder
- ✓Current treatment plan and functional assessment
Commonly Confused Codes
- •F29 — Unspecified psychosis is for when the type cannot be determined; F28 indicates a specific type was identified but does not fit standard categories
- •F20.89 — Other schizophrenia requires meeting full schizophrenia criteria; F28 does not
- •F22 — Delusional disorder involves only delusions; F28 may involve other psychotic features
- •F06.0/F06.2 — Psychotic disorders due to medical conditions should be used when an underlying medical cause is identified
- •F1X.950/F1X.951 — Substance-induced psychotic disorders should be used when substance etiology is established