Diagnosis · Checker
Principal Diagnosis Checker
Enter any ICD-10-CM code to check whether it's acceptable as a PDGM principal diagnosis or would return-to-provider. With the CMS acceptable-code file in place, every code is checked definitively; otherwise the tool screens by the PDGM coding rules.
Data statusBeta
- Status
- Beta
- Data year / effective
- ICD-10-CM FY2026
- Last reviewed
- June 2026
- Last updated
- June 2026
- Primary source
- ICD-10-CM (CMS/CDC); PDPM/PDGM grouper logic
- Known exclusions
- Not a substitute for the CMS grouper or payer validation
- Curated / partial mapping where the official file is not loaded
- ICD-10-CM updates annually (Oct 1)
Beta / Reference Only — not a substitute for the CMS grouper or payer validation.
Diagnosis code
A principal diagnosis is acceptable under PDGM only if it maps to one of the 12 clinical groups. CMS publishes roughly 43,000 acceptable primary diagnosis codes; everything else (about 29,000 codes) returns to provider — including some real disease codes such as ESRD (N18.6) and unspecified lung cancer (C34.90). That's why only the CMS list is definitive.
Two modes. Authoritative: when the file
/assets/pdgm-dx.json is present, the checker tests any code directly against the CMS acceptable-code list. Screening (default until that file is added): the checker applies the PDGM coding rules — symptom, external-cause, aftercare/status, manifestation, and injury-encounter patterns — plus a curated list of known return-to-provider codes. Screening is a guide, not the grouper.Need the clinical group instead of just acceptability? Use the ICD-10 → PDGM Mapper. PDPM has a parallel "Return to Provider" rule for the SNF primary diagnosis (MDS I0020B).
Examples of return-to-provider codes
| Code | Why it returns |
|---|---|
| M62.81 | Generalized muscle weakness — nonspecific; code the underlying cause. |
| R55 | Syncope and collapse — symptom code. |
| R26.9 | Unspecified abnormalities of gait and mobility — symptom code. |
| M54.50 | Low back pain, unspecified — nonspecific symptom. |
| M19.90 | Unspecified osteoarthritis, unspecified site — not assigned to a clinical group. |
| I10 | Essential (primary) hypertension — not assigned to a PDGM clinical group as principal. |
| N18.6 | End stage renal disease — not assigned to a PDGM clinical group as principal. |
| C34.90 | Malignant neoplasm of unspecified bronchus/lung — too nonspecific. |
| F03.90 | Unspecified dementia without behavioral disturbance — sequence the underlying etiology. |
| Z47.1 | Aftercare following joint replacement surgery — aftercare Z code; not acceptable as principal under PDGM. |
| Z51.5 | Encounter for palliative care — Z code; not acceptable as principal. |
| B95.62 | MRSA as the cause of diseases classified elsewhere — secondary-only organism code. |
