Cox regression analysis of potential confounding variables conducted for the TCGA (N = 122), GSE6891 (N = 439), and meta-cohort (N = 561).

Cohorts were limited to samples with complete records for all explanatory variables investigated. Results are shown for the (A) univariate Cox regression analysis per explanatory variable and (B) associated multivariate Cox regression analyses limited to confounding variables tested significant in univariate Cox regression analyses. Table columns are as described in Table 3. Analyses were performed for overall survival.