Quality assessment of tandem mass spectra based on cumulative intensity normalization.

A large proportion of MS/MS spectral analyses do not result in significant matches because their spectral quality is too poor to produce meaningful identification. Throughput of peptide identification can be greatly improved, if one can filter out, in advance, spectra that would lead to wrong identification. We introduce here an innovative approach to assess spectral quality utilizing a new spectral feature called Xrea, based on cumulative intensity normalization.