I'm conducting a meta-analytic structural equation model (MASEM) using the two-stage approach in
metaSEM in R. I have fit a model with two indirect effects, and would like to compare them to see if they differ in magnitude. Is it possible to constrain the indirect effects to equality so I can compare this model fit to the full model? Or is there some other way of testing differences between indirect effects?
Stage 2 R code here:
stage2total <- wls(Cov = cordat, aCov = Acov, n = sum(unique(SGMAdata.db$N)), Amatrix = A, Smatrix = S, diag.constraints = TRUE, intervals.type = "LB", mx.algebras = list( depindirectEffect = mxAlgebra(b21*b42, name="depindirectEffect"), indepindirectEffect = mxAlgebra(b31*b43, name="indepindirectEffect")) ) summary(stage2total)