Assigning significance to peptides identified by tandem mass spectrometry using decoy databases

Lukas Kall, John D. Storey, Michael J. MacCoss and William Stafford Noble

Journal of Proteome Research. 7(1):29-34, 2008.

---

Abstract

Automated methods for assigning peptides to observed tandem mass spectra typically return a list of peptide-spectrum matches, ranked according to an arbitrary score. In this article, we describe methods for converting these arbitrary scores into more useful statistical significance measures. These methods employ a decoy sequence database as a model of the null hypothesis, and use false discovery rate (FDR) analysis to correct for multiple testing. We first describe a simple FDR inference method and then describe how estimating and taking into account the percentage of incorrectly identified spectra in the entire data set can lead to increased statistical power.

---

Journal of Proteome Research
Home

---