The method involves arranging a calibrating system for prospective calibration of a measuring instrument. The calibration points are detected in the calibrating system. Each calibration point comprises a measurement signal of the measuring instrument and a reference value corresponding to the reference measurement. Multiple possible inclinations between the calibration points are determined. Independent claims are also included for the following: (1) a computer program with a program code； and (2) a measuring device for detecting an analyte in a body fluid.
