Hi all,

I have a longitudinal dataset with individuals some of which received a treatment at some time. What I want to do is to use propensity score matching and run a difference-in-difference regression. However, I have some questions about how to do this.

When I use the PSMATCH function it appears to me that the timing of the treatment plays no role and I simply compare individuals from the treatment and control groups. What I would initially like to do is to go to the year right before the treatment, match each individual with another individuals and then run the DID results. Does the IPWRA function do that? I did not have to specify a year though when trying to run the function. I am a bit lot on these two functions. Is there anyone who would have some recommendations?

Best,
Merve