Fig. 3

The altered fecal metabolites in the positive ion mode of the CPP group. A PLS-DA of CPP and healthy control groups. B The differential analysis between groups identified 1215 metabolites with significant differences and up-regulated and down-regulated metabolites with the top 20 largest differential degrees were marked. The outer circle colors of the dots indicated the different classifications of metabolites. C The abundance of 1215 metabolites. D The comparison of metabolites in steroid metabolic pathways between CPP and healthy controls. E The enrichment analysis of KEGG metabolic pathways based on differential metabolites and the enrichment significances were computed by hypergeometric distribution. The size of the point represented the enriched metabolites in pathways and the color of the point represented the differential abundance scores (*p < 0.05). F The abundance of the characteristic metabolites under positive ion mode of the classifier. G The performance evaluation of the random forest model according to the training set, test set, and training–testing set