01 · Source files
Raw inputs are stored in data/raw/us/{FY} and are never modified. Each fiscal year is parsed from the authoritative CMS document; TXT counterparts are used only as a second independent source for cross-validation.
| Fiscal Year | Rule | Source file | Sheet / Format |
|---|---|---|---|
| FY2023 | CMS-1771-F IPPS Final Rule | CMS-1771-F Table 5.xlsx | Single sheet |
| FY2024 | CMS-1785-F IPPS Final Rule | CMS-1785-F Table 5.xlsx | Single sheet |
| FY2025 | CMS-1833-F Correction Notice | FY2025 IPPS Final Rule & Correction Notice Table 5.xlsx | Sheet 0 (authoritative) |
| FY2026 | CMS-1833-F IPPS Final Rule | Table 5 addendum | Sheet 0 |
| FY2027 | IPPS Proposed Rule (FY27) | Table 5 addendum (proposed) | Sheet 0 · proposed values |
02 · Methodology decisions
FY2025 uses the Correction Notice, not the Final Rule.
CMS issued a correction to the FY2025 IPPS Final Rule. The Correction Notice supersedes the Final Rule where values differ. Sheet 0 of the combined xlsx file contains the Correction Notice values and is used throughout this pipeline.
Cap-applied weight is the operative reimbursement weight.
CMS introduced a 10% year-over-year weight change cap starting in FY2024. Where a cap was applied, two weight columns exist: Weights — Before Cap and Weights — 10% Cap Applied. This pipeline uses the cap-applied weight, consistent with actual Medicare payment. FY2023 has no cap structure and its single weight column is used as-is.
DRG restructuring is preserved, not masked.
Some DRG codes appear in only one or two of the covered fiscal years due to CMS restructuring (e.g., cardiac defibrillator DRGs 222–227 were consolidated into 275–277 in FY2024). These are flagged with restructured=True in Silver and Gold. Year-over-year deltas are computed only where a DRG exists in both comparison years.
03 · Validation statuses
Every DRG row carries a validation_status:
04 · QA summary
QA is performed by etl/qa_cms_pipeline.py. The current run reports 64 checks passed, 0 failed, 0 warnings.
05 · Dollar-impact model
Gold-layer outputs estimate reimbursement impact per DRG at volume tiers from 10 to 500 cases per year. Each estimate multiplies the FY-to-FY weight delta by a national standardized base rate.
06 · Known limitations
- Dollar-impact estimates use a national average base rate. Hospital-specific results will vary based on wage index, DSH adjustment, IME, and local market factors.
- OPPS (outpatient) data is staged but out of scope for this module. See the roadmap.
- This pipeline covers IPPS inpatient DRG weights only — not quality measures, VBP adjustments, or site-neutral payment policies.
- FY2023 is included for trend context. FY2027 values are proposed and will be replaced with Final Rule values when CMS publishes them.
- Anchor weight assertions currently cover FY2023–FY2025. FY2026 and FY2027 anchor checks are scheduled for the next QA pass.