Differential distribution of bacterial taxa that discriminate maximum pain levels in patients with recurrent abdominal pain. The distribution of bacterial taxa in patients with recurrent abdominal pain was used to classify the subjects based on the maximum levels of abdominal pain. Bacterial taxa (specified in leftmost column) were analyzed using randomForest and confirmed by feature selection using Boruta. The list is sorted first by Mann-Whitney U score followed by the largest disparity in medians for each group. Taxa represent the lowest taxonomic depth (Genus) that is labeled by RDP Classifier (at ≥ 80% bootstrap cut off). The degree of abdominal pain was differentiated by the maximum level of pain recorded during a 14-day period. Red rectangles display the HM (high- medium level) maximum abdominal pain phenotype. Light blue rectangles display the L0 (low-zero level) maximum abdominal pain phenotype. Boxes represent the first quartile, median, and third quartile of the distribution of OTUs for each pain group. Empty circles represent outliers that are 1.5x greater than the respective interquartile ranges. Shown are OTUs with increased levels of maximum pain in children with HM versus L0 maximum abdominal pain phenotypes.