Consensus clustering analysis for DRGs
Clustering analyses were performed using the “ConensusClusterPlus” R package, optimal k-clusters of DRGs were constructed by selecting k-values with high cluster stability based on the optimal clustering criteria. The optimal clustering criteria are as follows: the sample size of any group should not be too small; a decrease in the downward slope is observed in the cumulative distribution function (CDF) curve; and the intra-cluster correlation increases and the inter-cluster correlation decreases after clustering. Survival analysis was performed with the “survival” R package. Heat mapping using the "pheatmap" R package to analyze differences in clinical characteristics between clusters. The distribution of the samples among the different clusters was analyzed and plotted using the PCA algorithm and the “ggplot2” R package.