Fig. 3: The performance of microbial risk scores, clinical model, and comprehensive model.

A Comparison of the predictive performance (C-index) of all combinations of microbial risk scores derived from the three identified prognostic species in the test datasets using the Cox regression model. B Kaplan–Meier curves for PFS stratified by microbial risk scores (MRS) into low (n = 38), moderate (n = 150), and high-risk groups (n = 124). Numbers below the graph indicate patients at risk at different time points. The P value is calculated by the log-rank test. C Kaplan–Meier curves for overall survival stratified by the MRS. The P value is calculated by the log-rank test. D Comparison of the predictive performance (C-index) of all combinations of clinical factors (perineural invasion, lymphatic metastasis, and tumor stage) in the test datasets using the Cox regression model. E Performance comparison of the clinical model, MRS model, and comprehensive model (integrating both clinical and microbial factors) in the test datasets using the Cox regression model. The P value for the comparison between the clinical model and the comprehensive model was calculated using a Z score test. The bars represent the 95% confidence intervals calculated by the bootstrap method. F Performance comparison of the clinical model, MRS model, and comprehensive model in the test datasets using the random survival forest (Rsf) method. The P value for the comparison between the clinical model and the comprehensive model was calculated using a Z score test. The bars represent the 95% confidence intervals calculated by bootstrap method. T. mediumTreponema medium,N. oralisNeisseria oralis, C. gralisCampylobacter gralis, Mod moderate, Rsf random survival forest.