Historical pricing specs
The source record reaches back to 2012-13 for NEP determinations and national pricing model technical specifications. That year is caveated and is not treated as proof of a public calculator artifact.
Calculator coverage
This page summarizes the current source-to-code coverage story. It is a public docs view of the current implementation state, not a promise that every source artifact has been translated into executable code.
Historical pricing specifications, price weights, calculator artifacts, and NHCDC/costing evidence are tracked separately. The public archive reaches back to 2012-13 for pricing specifications, but calculator support is only claimed when an explicit calculator artifact and validation status exist. NHCDC or other costing materials are useful provenance, but they do not imply calculator support.
Classification input coverage is tracked separately from executable calculator
coverage. The phase 1 matrix work is documenting AR-DRG, AECC, UDG, Tier 2,
and AMHCC family transitions and licensed-input constraints. An initial shared
preflight validator exists in nwau_py.classification_validation, but this page
does not claim it is wired into calculator or CLI entry points end-to-end yet.
For admitted acute, AR-DRG outcomes are versioned outputs of ICD-10-AM, ACHI,
and ACS-coded episodes processed through licensed grouping tables or software;
the registry docs track compatibility and provenance, not a proprietary
grouper reimplementation.
2026-27 scope
NEP26 support exists and the 2026-27 calculator set is listed in the repository documentation, but this page does not claim parity validation against extracted IHACPA outputs unless tests explicitly establish it. Classification version impacts are clear: admitted acute moves to AR-DRG v12.0 from v11.0 through the licensed grouping workflow, and non-admitted moves to Tier 2 v10.0 from v7. AECC v1.1, AMHCC v1, AN-SNAP v5, and UDG v1.3 are unchanged from the previous year.
Implemented calculator families
Acute, ED, MH, subacute, outpatients, and adjustment logic are the active executable surfaces in the repository today. Admitted and community mental health remain separate validation surfaces underneath that family label.
Adjustment helpers
HAC, AHR, and complexity are currently modeled inside the adjustment pipeline, not as separate calculator binaries.
Source archive status
The archive manifest spans 2013-14 through 2026-27 and currently has 94 entries, 92 of which are downloaded.
Historical source matrix
Section titled “Historical source matrix”| Artifact family | Status | Notes |
|---|---|---|
| Pricing specifications | Documented | 2012-13 is the earliest confirmed year. It is a source-record year, not an implied calculator year. |
| Calculator artifacts | Implemented or gap-recorded | Public calculator downloads and executable surfaces are tracked separately from pricing specs. |
| Price weights | Documented or fixture-backed | Recorded as part of the year-specific pricing record, not as calculator support by themselves. |
| NHCDC / costing evidence | Documented | Useful for costing-study interpretation and provenance, but not calculator parity evidence. |
| AR-DRG grouping metadata | Documented | Versioned inputs and licensed grouping assets are tracked as provenance, not as a proprietary grouper implementation. |
| Validation status | Explicit | Use discovered, archived, extracted, implemented, fixture-tested, validated, and deprecated as the support gate. |
Executable calculator matrix
Section titled “Executable calculator matrix”| Family or helper | Status | Notes |
|---|---|---|
| Acute | Implemented | Current Python surface; Rust acute 2025 remains opt-in. 2026-27 classification impacts are AR-DRG v12.0 for admitted acute through licensed versioned grouping tables or software, and Tier 2 v10.0 for non-admitted. |
| Emergency department | Implemented | Current Python surface. |
| Mental health | Implemented | Current Python surface. |
| Community mental health | Implemented with validation gaps | Separate Python contract and calculator surface. NEP21-NEP24 are shadow-pricing inventory years; NEP25 is active. NEP26 exists for 2026-27 documentation coverage, but parity validation is not claimed unless tests prove it. Official golden fixtures are gap-recorded. |
| Subacute | Implemented | Current Python surface. |
| Outpatients | Implemented | Current Python surface. |
| Adjustment | Implemented | Includes HAC, AHR, and complexity outputs. |
| Complexity | Implemented as helper | Part of adjustment rather than a standalone calculator. |
| HAC | Implemented as helper | Part of adjustment rather than a standalone calculator. |
| AHR | Implemented as helper | Part of adjustment rather than a standalone calculator. |
| 2021-22 SAS Box page | Documented gap | Explicit box-html-only entry in the source archive. |
| 2022-23 SAS Box page | Documented gap | Explicit box-html-only entry in the source archive. |
What this means
Section titled “What this means”The repository can already explain its current calculator surface clearly:
- The core executable paths are present and tested.
- Historical pricing specs, price weights, and calculator artifacts are kept distinct from NHCDC/costing evidence.
- The remaining source gaps are recorded instead of being silently implied as missing or complete.