I want to match followers of some seed accounts with some random users on Twitter based on observed covariates using the coarsened exact matching method. My goal is to test whether following those seed Twitter accounts would change the outcome or not.
As for observed covariates, I can get, for example, # of tweets and # of followers. But these are post-treatment values, because the Twitter API gives me the current values of these variables. So can I use these post-treatment variables in my matching procedure, or I should only match on pre-treatment variables (e.g. # of tweets before the treatment, # of followers before the treatment, etc.)