Division 3.1.3.2 Power curve

The power curve provides information about the detection capability of the method within the chosen concentration range. It refers to the β-error risk when applying the investigated method. The power curve allows to calculate the detection capabilities for the respective categories (screening, confirmation) or types (qualitative or quantitative) of methods for a certain β-error (e.g. 5 %).

Figure 1

Power curve

Figure 1 shows an example of the graphical establishment of detection capability (CCβ) of an analytical method. This particular method has a remaining risk of taking a false decision of 5 % at a concentration of 0,50 μg/kg. At a concentration of 0,55 μg/kg the risk of taking a false compliant decision decreases to 1 %.