Hi,
I have a two-wave twin panel design (the same phenotype measured twice, two years apart for both twins) and I am planning on assessing stability. So far I have worked with Cholesky and the results seem interesting. However, I am really interested in biometric latent growth curve modeling. The obvious flaw would be that I only have two waves available. In the non-genetically informative literature LGC modeling is sometimes performed with only two waves, though no trend can be identified with the data. I am wondering, if I am doing a two-wave "biometric" LGC modeling design:
(1) does this make any sense? Or is cholesky (or maybe simplex) the better way?
(2) What are possible issues and limitations (in comparison to three or more waves)?
Thanks a lot in advance!