Lung Capacity Predicted Values (Spirometry Reference)

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Biology, Medicine & Pharmacology (educational estimates only — every panel labeled not-medical-advice)

Tranche

tranche-7

Evidence ID

t7-025

Ledger rows

1

No ledger note is attached.

Review findings

The arithmetic fixtures verify only ratio and percentage post-processing using explicitly supplied provisional reference values. They do not verify the GLI-2012 demographic prediction itself. Before PASS, supply the authoritative GLI-2012 coefficient/table dataset, source/version, ethnic-group mapping, LMS equation including z=0 convention, valid ranges, interpolation rules, missing-data behavior, rounding policy, and an explicit decision on whether %predicted for FEV1/FVC is offered.

Formula and scope findings

• The specification names GLI-2012 but does not provide the required GLI-2012 LMS coefficients, spline knots, coefficient version, or calculation algorithm, so the claimed predictions cannot be independently reproduced from this specification.
• GLI-2012 is ordinarily implemented with sex-, age-, height-, and ethnic-group-specific L, M, and S parameters and z-score equations; a generic lookup-table description is insufficient unless the exact table and interpolation rules are supplied.
• The permitted ethnicity categories and mapping are unspecified. GLI-2012 uses defined reference groups, and an arbitrary ethnicity label or race/ethnicity mapping can produce materially different results.
• The specification does not state whether age is decimal years or completed years, whether height is standing height in centimetres, or which sex definition and valid age range are used.
• It is ambiguous whether predicted FEV1/FVC means the quotient of predicted FEV1 divided by predicted FVC or a separately predicted GLI-2012 ratio/z-score quantity.
• %predicted is not generally a clinically appropriate summary for FEV1/FVC; the ratio is commonly interpreted with its own reference distribution or z-score, not simply as a percentage of predicted ratio.

Unit assumptions

• Age is assumed to be in years and within the validated GLI-2012 range of approximately 3 through 95 years.
• Height is assumed to be standing height in centimetres; no automatic conversion from inches is assumed.
• FVC and FEV1 are assumed to be in litres (BTPS-adjusted spirometric values).
• Ratios are dimensionless and are reported here as a decimal rather than a percentage.
• The provisional table rows below are explicit test fixtures for arithmetic and post-processing only; they are not a substitute for the missing official GLI-2012 coefficient tables.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The specification cannot produce numerical predicted FVC, FEV1, or ratio outputs because the required GLI-2012 coefficient tables and exact validity/switch definitions are missing. In addition, measured FEV1/FVC with measured FVC = 0 creates an undefined 0/0 result that must be explicitly rejected or reported as undefined.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "age_years": 25,
    "height_cm": 180,
    "sex": "male",
    "ethnicity": "Caucasian",
    "measured_FVC_L": 5,
    "measured_FEV1_L": 4
  },
  "expected_outputs": {
    "predicted_FVC_L": 5.5,
    "predicted_FEV1_L": 4.4,
    "predicted_FEV1_FVC_ratio": 0.8,
    "FVC_percent_predicted": 90.91,
    "FEV1_percent_predicted": 90.91
  },
  "reference_data": {
    "predicted_FVC_L": 5.5,
    "predicted_FEV1_L": 4.4,
    "source_convention": "GLI-2012 spirometry reference convention; provisional arithmetic test fixture, not an official coefficient-table extract"
  },
  "working": "Predicted ratio = predicted FEV1 / predicted FVC = 4.4 / 5.5 = 0.800000. FVC %predicted = 5.0 / 5.5 x 100 = 0.9090909 x 100 = 90.91%. FEV1 %predicted = 4.0 / 4.4 x 100 = 0.9090909 x 100 = 90.91%."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche7/tranche7-results.json
• BOUNDARY_HAZARD_CATALOG.json