How to combine overall ROC curve and stratified ROC curve into one graph?

[Xingru He]

Dear Stata Community,

I have three key variables:
A binary Gold standard classification variable (Actual outcome of credit card late payment status)
A binary Tested classification variable (Predicted outcome of credit card late payment status)
A binary category variable (Age above 30 and age below 30)

I hope to construct a ROC graph with three ROC curves.
1. An overall ROC curve including everyone.
2. A ROC curve among those above 30.
3. A ROC curve among those below 30.

I need your suggestions and help. Thank you in advance!

Sincerely,