Provided are a process and a device for the qualitative and/or quantitative determination of a protein and/or peptide pattern of a liquid sample taken from a human or animal body for checking its state. The peptides and proteins of the liquid sample are processed and then subjected to analysis, wherein reference and sample values describing states of a human or animal body as well as deviations and correspondences derived therefrom are established, automatically stored in a data base, and when the protein and/or peptide pattern is again determined, a search for optimum correspondence is automatically performed. In this process, mass components or structural components of the proteins and/or peptides are established and stored. Subsequently, real masses or real structures are calculated from a common evaluation of the stored mass components or structural components, and an assignment to the proteins and/or peptides contained in the liquid sample is performed from a combination of the calculated real masses or real structures.