How to include dependent events in proc phreg

[Alireza_Boloori]

Hello everyone,

I want to do survival analysis with dependent events (i.e., when there are multiple events for each patient, and any event is not independent of the previous event). Based on what I've observed, I think I need to use "strata" for different time intervals (for example, please see "conditional model A" and the table shown in this tutorial https://stats.idre.ucla.edu/sas/faq/how-can-i-model-repeated-events-survival-analysis-in-proc-phreg/).

Footnote: there may be other ways to adjust dependent events that I'm unaware of. Please direct me if you know anything in this regard.

However, in my data, I also have other risk factors (e.g., age, gender), for which I want to consider another type of strata (please see https://support.sas.com/documentation/cdl/en/statug/63033/HTML/default/viewer.htm#statug_phreg_sect0...). So, my question is that how can I accomodate these two types of strata in "proc phreg"?

Thank you for your thoughts/feedback!