[R] Stat question mixed models with time varying covariate

[Peter Flom]

Please xcuse me for being slightly off-topic and cross-posting

I have a data set of schools, with scores for 4 years.  The goal is to evaluate the effect of an intervention on the scores, accounting for some covariates which are not problematic.  The chief problem is that the intervention could take place in any or all of the 4 years.

I've thought of doing separate analysis for each pair of years, but this has all the problems associated with pre- post- designs, and results in multiple models to interpret.

Is there a way to use mixed models here?

I've tried googling but found little

TIA

Peter

Peter L. Flom, PhD
Statistical Consultant
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