Extended Cox PH Model in complex survey design setting (PROC SURVEYPHREG)

[_MooMoo]

Hello SAS community, 

I am posting this question to get some advice from you.

I am trying to run extended Cox PH model that allows for recurrent time-to-event data. However, data were collected using stratified random sampling method. I navigated PROC SURVEYPHREG, but it doesn't have an option to allow for recurrent time-to-event data. However, PROC SURVEYREG has that option to run extended Cox PH model. 

In this case, is it valid to run PROC SURVEYREG even though data were collected using stratified random sampling method (complex survey design)? In practice, do we just assume simple random sampling?

Any kind of advice is welcome!