Untargeted metabolomics analysis of metabolite changes in gastric cancer patients from plateau regions

Figure 5 Fecal metabolomics analysis of orthogonal partial least squares discriminant analysis between gastric cancer group and healthy group. A: Permutation plot test results of the orthogonal partial least squares discriminant analysis (OPLS-DA) model comparison between healthy group (CK) and gastric cancer group (DG) groups (permutation plot test of OPLS-DA model for group CK vs DG). The X-axis shows the permutation retention (proportion consistent with the original model's Y variable order, where a point at 1 represents the original model's R2Y and Q2 values), while the Y-axis displays the values of R2Y or Q2. Green dots indicate the permutation test-derived R2Y values, blue squares represent the permutation test-derived Q2 values, and two dashed lines show the regression lines for R2Y and Q2; B: Permutation histogram test results for the OPLS-DA model comparison between CK and DG groups (CK vs DG). The X-axis shows the accuracy rate of the randomized model in permutation tests, while the Y-axis indicates the number of random models. Red bars represent the frequency of Q values obtained through permutation tests, and blue bars show the occurrence count of R_Y values. P < 0.05 indicates optimal model performance.