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## Comments

CIC is a nice approach in many applications

Though it is less commonly used in empirical work than DID.

Need to estimate quantiles

Harder to include covariates (due to needing to estimate quantiles). I think (not 100% sure though) that it is not possible (at least not obvious) if one can do a doubly robust version of CIC.

Support conditions can have real bite in some applications

Not as much software support