sas >> Ramdom Effects Predictors for Cox Regression Model

by Karovaldas » Sat, 13 May 2006 21:25:32 GMT

Is is possible to incorporate random effect into a Cox Regression model
using SAS? I am thinking of a multicenter trial where time-to-event is
an outcome. Using sites as fixed effects is an option; however, the
differences between sites are really random, not fixed and should be
modeled accordingly.

Is there a provision for such analysis in SAS and, if not, can someone
explain why?

How does parametric vs. non-parametric distinction apply in this case,
if it does?

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