Methodology · Version 1.0

How every number gets from CMS to the dashboard.

This document describes the source files, parsing decisions, validation checks, and assumption sets that sit behind DRG Weight Intelligence. Everything below is published. Nothing is proprietary.

Module · DRG Weight IntelligenceCoverage · FY2023 → FY2027 · five Final RulesArchitecture · Bronze → Silver → Gold

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 YearRuleSource fileSheet / Format
FY2023CMS-1771-F IPPS Final RuleCMS-1771-F Table 5.xlsxSingle sheet
FY2024CMS-1785-F IPPS Final RuleCMS-1785-F Table 5.xlsxSingle sheet
FY2025CMS-1808-F Correction NoticeFY2025 IPPS Final Rule & Correction Notice Table 5.xlsxSheet 0 (authoritative)
FY2026CMS-1833-F IPPS Final RuleTable 5 addendumSheet 0
FY2027CMS-1849-F IPPS Final RuleTable 5 addendumSheet 0

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:

confirmedAnchor DRG (001, 003, 470) — weight verified against a hardcoded known value.3 per FY
plausibleNormal data — no anomalies detected across cross-source or delta checks.majority
flaggedYoY weight change exceeds ±15% — legitimate but warrants manual review before financial use.46
manual_reviewDRG 998 / 999 (Ungroupable / Invalid Discharge) — no weight by definition.2

04 · QA summary

QA is performed by etl/qa_cms_pipeline.py, which reports 74 passed, 0 failed, 0 warnings. That script is one of twelve gates run by etl/run_qa.py; the release invocation --require-raw reports 12 / 12 with zero skips. Any gate failure is a non-zero exit, so a build cannot ship past a red check.

Cross-source (TXT vs XLSX)
765 / 764 / 771 / 770 / 766
DRGs matched exactly across FY23 / FY24 / FY25 / FY26 / FY27 — every year, zero discrepancies
Row counts vs CMS totals
767 / 766 / 773 / 772 / 768
All five fiscal years matched CMS published totals (gap of 2 = DRG 998/999)
Anchor weight assertions
15 / 15 passed
DRG 001, 003, 470 against hardcoded CMS-published weights — all five fiscal years, FY23 through FY27
Dollar-impact math
30 / 30 passed
Per-case and volume-tier amounts verified

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.

Default base rate: $6,848.98 — CMS FY2027 IPPS national operating standardized amount (CMS-1849-F, Table 1A: $4,520.33 labor + $2,328.65 non-labor). An automated check re-reads that workbook and refuses to build if the configured rate stops matching it. This is a national average and does not account for hospital-specific adjustments including wage index, DSH, IME, or outlier payments. Hospitals should substitute their own case-mix-adjusted rate for precision analysis.

06 · Known limitations

07 · Disclaimer

This tool provides informational analysis of publicly available CMS regulatory data. It is not intended as legal, billing, compliance, or financial advice. Hospitals should consult qualified revenue-cycle professionals and legal counsel before making operational or financial decisions based on this information. Data accuracy is not guaranteed.