[R] Multi-level (nested) correlation structures via geepack package

Phat Chau
Sun, 12 Jul 2020 13:52:18 -0000

Hello,

I have a multi-level, cohort dataset with three levels: repeat measures of a
response (level 1), that are collected from individual participants (level 2)
who are students within a school (level 3). I would like to do a generalized
estimating equation (GEE) analysis of this clustered data, but to do so I need
to specify ?nested? correlation structures (e.g. exchangeable, compound
symmetric, Toeplitz) to account for the within-individual and within-cluster
correlations.

Here is a reference paper that describes a nested exchangeable correlation
structure and nested compound symmetry: doi:10.1111/j.1541-0420.2009.01374.x.

The geepack is available in R to do GEE analyses, but it seems to me that it
only allows the user to specify a correlation structure via the geepack(??corstr
= ?) option which only accounts for the within-individual correlations (that
arise from repeated measures). Would it be possible to specify the nested
correlation structures that I refer to here to also account for the
within-cluster correlations using this package?