R99-R99 — Ill-defined and unknown cause of mortality
Every ICD-10-CM code in this range and the PDGM clinical group CMS assigns to it, read from the CMS grouper crosswalk v07.1.26.
Codes in range
1
No clinical group
1
A period cannot be grouped from these.
Barred as primary
0
CMS rejects these in the primary position.
Where these codes group
None of the 1 codes in R99-R99 is assigned a PDGM clinical group. A 30-day period cannot be grouped from any of them, so none can hold the primary position on a home health claim.
Every code in R99-R99
Descriptions are CMS’s own, abbreviated as CMS abbreviates them.
| Code | Description | Clinical group | Primary position |
|---|---|---|---|
| R99 | Ill-defined and unknown cause of mortality | None | Cannot group |
Source: CMS HH PPS Grouper Software v07.1.26, effective 2026-04-01. 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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