F90.9
BillableAttention-deficit hyperactivity disorder, unspecified type
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is F90.9 an HCC code?
No. F90.9 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
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 F90.9
For F90.9to 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 F90.9 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
F90.9 is the ICD-10-CM diagnosis code for attention-deficit hyperactivity disorder, unspecified type. Attention-deficit hyperactivity disorder where the specific presentation type (inattentive, hyperactive, or combined) has not been determined or documented. F90.9 sits in the ICD-10-CM chapter for mental, behavioral and neurodevelopmental disorders (f01-f99), within the section covering behavioral and emotional disorders with onset usually occurring in childhood and adolescence (f90-f98).
F90.9 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
F90.9 does not map to any HCC in V28 or V24 models. RxHCC maps to 133 (0.000). No RAF score contribution. Query for subtype specificity whenever possible for optimal clinical documentation. Coders reviewing F90.9 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC — capturing the correct specificity is the highest-leverage RAF improvement available within accurate coding.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for F90.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use only when type cannot be determined from available documentation; query provider for clarification when possible
- •This code should be temporary; aim to specify the ADHD subtype with additional clinical information
Clinical Significance
Unspecified ADHD is used when the provider documents an ADHD diagnosis without specifying the subtype (inattentive, hyperactive-impulsive, or combined). While clinically acceptable, subtype specification improves treatment planning and medication selection. This code is commonly seen when ADHD is documented in problem lists or by non-psychiatry providers without detailed subtype assessment.
Documentation Requirements
- ✓Provider documentation of ADHD diagnosis
- ✓Evidence of inattention and/or hyperactivity-impulsivity symptoms
- ✓Query opportunity — attempt to obtain subtype specification from the provider
- ✓Documentation of functional impairment
- ✓Current treatment plan
Commonly Confused Codes
- •F90.0 — ADHD, predominantly inattentive type; use when inattentive subtype is documented
- •F90.1 — ADHD, predominantly hyperactive type; use when hyperactive subtype is documented
- •F90.2 — ADHD, combined type; use when combined subtype is documented
- •R41.840 — Attention and concentration deficit; this symptom code should not be used when ADHD is diagnosed