Abstract: A method is disclosed for calculating and recalculating protein confidence values by recalculating peptide confidence values in proteomic analysis. A plurality of scans are performed of a sample that is proteolytically digested into surrogate peptide analytes. A plurality of spectra are obtained, and a plurality of peptides are identified. A protein database is searched for proteins matching peptides from the plurality of peptides. Peptide confidence values are determined for the set of peptides. A protein confidence value is calculated for each protein in the set of proteins. A protein from the set of proteins with a largest protein confidence value is selected, the largest protein confidence value for the protein is saved, the protein from the set of proteins is removed, and peptides corresponding to the protein is removed from the set of peptides. The protein confidence value is recalculated for each protein in the set of proteins.