I am working on a measurement invariance paper. The scale I'm using is ordinal, with a 5-point scale. So, I have run the models with the ordered command, rather than treating the data as continuous.
To evaluate invariance, I am triangulating the change in fit indices and examining the change in chi-square. I know that chi-square is sensitive to sample size. But, I have unequal group sizes, and know from Chen (2007) that unequal group sizes or invariance patterns can bias the fit indices.
Because my data are ordinal, I am interpreting the robust estimates rather than DWLS. When I run lavTestLRT, it compares the DWLS chi-square values rather than the robust estimations.
Does anyone know of a method to compare the robust test statistics? If it can't be done with lavaan, does anyone know of a workaround or know how to compute this?