A computer device includes memory that stores a test plan for a coordinate measuring machine to perform an object measurement. The test plan includes at least one test feature for a plurality of reference elements of the object. The computer device includes at least one processor configured to execute instructions stored in the memory. The instructions include, for each of the reference elements, obtaining at least one accuracy variable. The accuracy variable specifies an accuracy of the measurement result of a respective reference element. The instructions include ascertaining an error effect of each reference element on the quantification of the test feature based on the respective accuracy variable. The instructions include ascertaining for each of the error effects whether it meets an error criterion and, if so, classifying a reference element assigned to this error effect as a critical reference element.