Combined AUC

Hi everyone, I'm new here

I'm doing on my medical thesis. I have 3 variables:
A: Value of a biomarker
B: Value of a Risk score
C: Survival (binominal)

I want to draw a combined AUC for A (biomarker) +B (risk score), to see if that increase AUC of any single A or B
Could someone help me please?


Not a robit
Not versed in SPSS. Would imagine worse case you can fit all three models and output AUC values and crudely compare. I know SAS has an easy process to compare AUC's between models in their logistic regression procedures. Good luck.