After calculating all dEMD values for the mono-iso pairs of both the TP and TN cases, the TP and TN probability percentage distributions were obtained for the selected elemental ratios (Figure ). For the TP probability distributions, there were 2 regions for which the TP probabilities were higher than the TN probabilities. The first region being around a dEMD of 0, which is in accordance with the hypothesis that the monoisotopic and isotopologue mass of the same compound obtain similar EMD values. As for the second region, dEMD values close to 1 and -1 Da were found. For the TN probability distributions, a small decrease in probability was observed around a dEMD of 0 Da, which was caused by the minimum added mass error to the isotopologue mass of the TN mono-iso pairs (i.e., 0.01 Da). Overall, these plots showed that the dEMD could be used to differentiate between isotopologue and non-isotopologue masses.