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How is PS matching incorporated into a model?

Researchers
#1

Hello.

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?

#2

Please see the CohortMethod vignette for details on how to use the PS matching.

#3

I had already read that vignette.
There the PS is used internally by the OHDSI tools.
It seems it creates a subpopulation by matching people, and discards the remaining ones. Isn’t it?

But I’m asking how to get the same results with common packages such as glm, lme4, survival… How do I introduce the PS matching in models created with those packages?

#4

If it was easy to do with existing packages we wouldn’t have created our own.

t