Waist-to-Hip / Waist-to-Height Ratio mechanism

Model scope

The arithmetic formulas pass standard dimensional checks, but the instrument is not fully specified because its required risk-band output cannot be determined from the provided data. Verdict is NEEDS_REVIEW until exact thresholds, band labels, demographic applicability, and measurement protocol are defined.

• WHR=waist/hip and WHtR=waist/height are standard dimensionless ratio formulas when all measurements use the same unit.
• The risk-band output is underspecified: no threshold table, threshold values, band names, or mapping rules are provided.
• The claimed WHO risk threshold bands are ambiguous because applicable thresholds may depend on sex, age, population, measurement protocol, and whether the indicator is WHR or WHtR.

Units and conventions

• Waist, hip, and height must be measured in the same unit before division; centimeters, meters, or inches are each acceptable if used consistently.
• The ratios are dimensionless, so converting every input by the same factor does not change the result.
• Waist and hip are assumed to be circumference measurements taken using a defined anthropometric protocol; the measurement sites are not specified.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "waist": 80,
    "hip": 100,
    "height": 170,
    "unit": "cm"
  },
  "expected_outputs": {
    "WHR": 0.8,
    "WHtR": 0.4705882353,
    "risk_band_label": null
  },
  "working": "WHR = waist / hip = 80 / 100 = 0.8. WHtR = waist / height = 80 / 170 = 8 / 17 = 0.4705882353. Risk band = undetermined because no threshold table or mapping is supplied."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The specification exposes undefined results when hip or height is zero, does not define the risk-band threshold table or branch conventions, and leaves unit normalization unspecified; mixed units can therefore produce a numerically valid but physically nonsensical WHtR.

Other records

Sources and evidence

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

• VERIFIED_LEDGER.json
• evidence-tranche3/tranche3-results.json
• BOUNDARY_HAZARD_CATALOG.json