Do SAT-optional policies matter?

Not really:

Despite many conversations regarding the applicability and relevance of the SAT as a valid admissions tool, there is limited evidence regarding the effects of test-optional policies on various aspects of an institution’s effectiveness and the collegiate experiences within each institution. Using data from the Integrated Postsecondary Education Data System (IPEDS) coupled with a difference-in-difference analysis, we find that test-optional policies have very limited effects. We find SAT optional policies to have no significant effect on diversity or enrolled student quality. The only statistically significant effect we find is a brief increase in the number of applicants in response to the new policy.

That is from Matt Saboe and Sabrina Terrizzi, in Economics Letters, via the excellent Kevin Lewis.