Transparency · CHAI Applied Model Card
Vitamin D Deficiency + Calcium dysregulation
CHAI Applied Model Card (v0.1) for the Vitamin D Deficiency + Calcium dysregulation pattern in Zenlo Labs. This document is not CHAI-certified or CHAI-endorsed.
Header
Summary
This combined pattern addresses vitamin D status and calcium–parathyroid hormone dysregulation in adult laboratory panels — the clinical pairing used in Zenlo Labs production merge logic. A vitamin D deficiency detector flags low 25-hydroxyvitamin D against registry thresholds; a separate calcium/PTH detector evaluates hyper- or hypocalcemia patterns with elevated or suppressed PTH. Either sub-detector firing surfaces the merged pattern. Claude Haiku 4.5 synthesizes narrative context on mineral and hormonal balance for physician review. For licensed functional-medicine physicians, this is supportive clinical decision support — it does not assess bone density, renal osteodystrophy, or malignancy-related hypercalcemia workup. Outputs highlight laboratory mineral signals requiring clinical correlation.
Uses & Directions
Intended use
Clinical decision support for licensed physicians evaluating vitamin D, calcium, and PTH patterns in adult panels.
Primary users
Licensed functional-medicine physicians and similarly qualified clinicians.
How to use
Review flagged mineral markers with dietary intake, sun exposure, malabsorption history, and bone health context.
Target population
Adults aged 18 and older in the United States.
Out of scope
- Direct patient use without physician oversight
- Pediatric rickets or infant calcium disorders
- Standalone diagnosis of hyperparathyroidism or malignancy
- DEXA or bone-density interpretation
Warnings
Clinical risk level
Low — supportive tool; the treating physician retains full clinical judgment and responsibility.
Known limitations
- Vitamin D assay methods and reference ranges vary across laboratories.
- Calcium interpretation requires albumin correction in some clinical contexts — not automated here.
- PTH reference ranges depend on concurrent calcium and renal function.
Validation note
Validation pending — a Tier A NHANES validation run has not yet been completed for this pattern. Distribution, agreement, and fairness results will be published here when available.
Trust Ingredients
AI system facts
- Deterministic pattern detector (vitamin_d_deficiency) plus Claude Haiku 4.5 for narrative synthesis
- Primary inputs: 25-hydroxyvitamin D, serum calcium, and parathyroid hormone from structured extraction.
- Output: Merged pattern flag plus narrative on vitamin D and calcium/PTH findings.
Security & compliance
- Anthropic Business Associate Agreement with zero-data-retention configuration
- HIPAA-aligned design; no patient data used for model training
Ongoing maintenance
Versioned, transparent, and reproducible via a public independent audit harness (see Resources).
Transparency
Self-funded development; no third-party sponsor for this pattern card.
Key Metrics
Usefulness / Efficacy
Zenlo’s detection approach was benchmarked across five models in a separate study; see the medRxiv preprint in Resources. No per-pattern efficacy metric is published for this pattern. Source: 5-model benchmark, medRxiv MEDRXIV/2026/346284.
Fairness / Equity
Validation pending — a Tier A NHANES validation run has not yet been completed for this pattern. Distribution, agreement, and fairness results will be published here when available.
Safety / Reliability
- Supportive-only; not intended as a standalone diagnostic
- Physician authorization required before clinical use
- Deterministic detector is reproducible for inputs: VITD, CALCIUM, PTH
Resources
- medRxiv preprint MEDRXIV/2026/346284 — 5-model benchmark (system-level detector evaluation)
- JAMIA Open submission JAMIO-2026-0120 (under review)
- Independent audit harness: github.com/dimashibakov/zenlo-audit — reproducibility manifest, NHANES 2015–2016 cycle, harness commit c10afe8
Note: The mention or sharing of any examples, products, organizations, or individuals does not indicate any endorsement by the Coalition for Health AI (CHAI). Zenlo Labs is a clinical decision support tool intended exclusively for use by licensed healthcare providers — not a substitute for professional medical judgment, and not intended for direct patient use.