st: GEE and likelihood ratio test

[Raoul Reulen <r.c.reulen@bham.ac.uk>]

Hello All,
 
I'm running a logistic regression model with a GEE modification. I understand that I cannot use a likelihood ratio test to test whether there is heterogeneity accross the odds ratios. What is the alternative? A wald test using .testparm? Would this give me the p-value for test for heterogeneity?
 
.xi: xtlogit status i.covar1  , pa corr(exch) i(id) robust eform
.testparm _Icovar*
 
Thanks 
 
Raoul
 
 
Raoul Reulen
Cancer Research UK Graduate Training Fellow
Centre for Childhood Cancer Survivor Studies
Department of Public Health & Epidemiology
University of Birmingham
Birmingham
B15 2TT
tel.: +44 (0)121 414 4946
fax.: +44 (0)121 414 7923
email: r.c.reulen@bham.ac.uk
website: www.bccss.bham.ac.uk <http://www.bccss.bham.ac.uk/> 


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