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Medical ImagingGenerated accuracy model review: 2026-05-06

Contrast Clearance (CrCl) accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • The Cockcroft-Gault equation estimates GFR based on creatinine production (linked to age/weight) and excretion (serum levels). **Men:** ((140 - Age) × Weight kg) / (72 × SerumCr) **Women:** Result × 0.85

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Sex: Male
  • Age: 50 years
  • Weight: 75 kg
  • Serum Creatinine: 1 mg/dL

Expected outputs

  • Creatinine Clearance: 93.8 mL/min
  • Interpretation: Normal range

Known limitations

  • Less accurate for unstable renal function (AKI). Use caution in extremes of age or body size, and defer to local contrast policies when thresholds differ.

Assumptions

  • The result is a Cockcroft-Gault estimate and may differ from lab-reported eGFR values.
  • The calculator assumes a stable serum creatinine and is less reliable in acute kidney injury or rapidly changing renal function.
  • Contrast decisions depend on the full clinical context, exam urgency, and institutional protocol, not this number alone.

Unit handling

  • Sex accepts one of the configured options.
  • Age accepts values in years.
  • Weight accepts values in kg.
  • Serum Creatinine accepts values in mg/dL.
  • Creatinine Clearance is displayed in mL/min.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current creatinine-clearance-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Contrast Clearance (CrCl).

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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