We used a Cholesky decomposition model (six A factors, six C factors, and six E factors) for these analyses, as this structure allows us to impose a temporal structure on the manifest variables (from left to right as time progresses). This enabled us to evaluate whether new latent A (or C) influences ‘ come online’ over time. We compared submodels in which later (epoch 2–6) C and A factor loadings were sequentially removed from the model using the p value of the χ2 and Akaike’s Information Criterion (Akaike, 1987) as an indicator of model fit and parsimony. We did not test the significance of E factor loadings, as such tests were peripheral to our research question and could result in over-fitting. Thus, the structure of E factor loadings remained saturated throughout the model-fitting process.
