Propensity Score (PS) matching can be done using the the nearest neighbour method: one unexposed subject with one (or more) exposed subject with similar PS.
Once I have calculated the PS and I have matched the subjects…
How do I introduce this information into the model? (For example with the package lme4).
Or it can only be done with special packages such as Cyclops and MatchIt?
Do I just need to add the PS term in the model?
logit(Outcome) ~ Treatment + PS
Do I also need to add the pair or cluster as a random effect?
logit(Outcome) ~ Treatment + PS + (1|cluster)
Or all I need to do is to subsample the original dataset keeping just matched pairs and discard unmatched people?