I am comfortably able to run a Bayesian multilevel mediation model via the bmlm package’s bmlm function which makes it very easy to run (uses RStan interface). However, it does not appear to have the functionality for running a moderated multilevel mediation model. Does anyone have any intuitions about how best to run a moderated multilevel mediation model via bmlm or RStan? My only best guess at this moment is to subset condition 1 and condition 2 of the dichotomous group moderating the mediation and running bmlm for the two groups and compare effects that way. But I’m not sure if that’s the best or most effective way to do a moderated multilevel mediation in RStan or bmlm. Anyone have any thoughts?