I\'m new in metabolomics, but familiar with mass spectrometry based proteomics. Recently, I read the new call from Metabolite Identification Task Group to improve current standard system for reporting metabolite identification results (Creek D, Dunn W, Fiehn O, Griffin J, Hall R, Lei Z, et al. Metabolite identification: are you sure? And how do your peers gauge your confidence? Metabolomics. 2014;10:350-3.). My suggestion is, since the rank of candidate molecules is represented by scores or probabilities, the confidence of the first rank can be estimated by the p-value or E-value which indicates how far the highest score is from the distribution of other scores hypothesized as random distribution (this hypothesis is based upon that other candidates are wrong, thus randomly selected by the algorithm). For untargeted analysis, this problem becomes a multiple testing problem that can be estimated by false positive rate/false discovery rate.