Biomarker of choice to discriminate between conditions. Selected pair wise comparisons of conditions are represented taking into account the difficulty of diagnosis or the risk of progression. The four options of biomarkers (F. prausnitzii, the two phylogroups or the F. prausnitzii-E. coli index calculated as (Lopez-Siles et al., 2014)), have been ranked according to their discriminative power estimated as the sum of all the AUC values for all the pair wise comparisons taking into account all the conditions. For each comparison, the highest AUC value achieved is depicted. H, healthy control group; F, total F. prausnitzii load; PHG I, F. prausnitzii phylogroup I load; PHG II, F. prausnitzii phylogroup II load; F-E index, F. prausnitzii- E. coli index; AUC, area under the ROC curve; ROC, receiver operating characteristic curve.