A mass spectrometry method comprises: acquiring a series of survey mass spectra of first-generation ions generated from a sample; acquiring a series of fragment-ion mass spectra, each being a record of a respective set of fragment-ion species generated by fragmentation of a respective subset of the first-generation ions within a respective mass-to-charge isolation range; adjusting mass spectrometer operational parameters used to acquire a later one of the survey mass spectra based on results of an earlier one of the survey mass spectra; dividing the acquired series of fragment-ion mass spectra into a first group wherein an appearance of a fragment-ion species correlates with the appearance of a first-generation ion species observed in a survey mass spectrum and a second group wherein no obvious correlation is observed between fragment-ion species and first-generation ion species; and mathematically processing the spectra of the first and second groups by different mathematical procedures.