Receiver Operating Characteristic Curves and Uncertainty of Measurement

healthy population

mean

0

standard deviation

1

diseased population

mean

2

standard deviation

1

uncertainty of measurement

first test

0.2

second test

0.6

This Demonstration compares two receiver operating characteristic (ROC) plots of two diagnostic tests (first test: blue plot, second test: orange plot) measuring the same measurand. The comparisons are for normally distributed healthy and diseased populations, for various values of the mean and standard deviation of the populations, and of the uncertainty of measurement of the tests. A normal distribution of the uncertainty is assumed. The ratio of the areas under the ROC curves of the two diagnostic tests is calculated. The six parameters that you can vary using the sliders are measured in arbitrary units.