st: gllamm or SVY

["Irene Moral" <imoral@eapsardenya.cat>]

Dear all,

I'm analysing a sample drawn from a stratified cluster designed study.

In my study, I considered countries as strata, health centers in each 
country as clusters and then patients are selected within each cluster.

I'm using the svyset and all the svy commands to define the sample design 
and to run analysis, but some people asked me about using multilevel 
analysis instead of svy.

I have understood that other options are to use the gllamm command or to 
panel data as longitudinal and use xt commands, ¿it is true?

can anybody explain in which cases is more useful to use one than the other? 
or what type of errors am I exposed to when using svy?

thanks in advance

Irene 

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