ICD-10 · PDGM grouping
Q04 Other congenital malformations of brain
All 9 codes in the Q04 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
9
Can lead a claim
0
Cannot lead a claim
9
What CMS assigns to Q04
None of the 9 codes is assigned a clinical group. None of the 9 is assigned a comorbidity subgroup. None can lead a claim.
Every code in Q04
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| Q04.0 | Congenital malformations of corpus callosum | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.1 | Arhinencephaly | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.2 | Holoprosencephaly | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.3 | Other reduction deformities of brain | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.4 | Septo-optic dysplasia of brain | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.5 | Megalencephaly | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.6 | Congenital cerebral cysts | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.8 | Other specified congenital malformations of brain | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| Q04.9 | Congenital malformation of brain, unspecified | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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