Babels.AI

Methods

Calibration of a prediction model

Also called: calibration curve, Brier score, calibration slope, ECE

A calibrated model's predicted risks match observed rates: of patients given a 20% risk, about 20% have the event. Calibration matters as much as discrimination for clinical use.

Calibration asks whether predicted probabilities can be taken at face value. It is usually shown as a calibration curve plotting predicted risk against observed event rates, and summarized with the calibration slope (ideally 1), calibration-in-the-large, expected calibration error (ECE) or the integrated calibration index (ICI).

The Brier score, the mean squared difference between predicted probability and actual outcome, combines calibration and discrimination into one number; lower is better.

Poor calibration is common when a model is trained on one population and applied to another, which is why external validation and recalibration matter before any prediction is used to inform care.

Tools that use this

Related terms

Educational reference. Not medical advice and not for clinical decision-making.