Abstract: In a method to reliably avoid erroneous length determination in the analysis of an image, in particular a digital patient image formed in the course of a medical imaging examination method, by automatic scaling or by the scaling verification of such an image, a shape segment inside the image range of the image is identified and selected by electronic image processing, at least one classification parameter determined according to predetermined criteria is assigned to the shape segment, at least one reference segment comparable to the classification parameter or parameters is selected from a reference database, the size of the shape segment is evaluated using the selected reference segment, and an evaluation quantity characterizing the result of this evaluation is formed.