Standardized effect size (you can also use this for baseline equivalence test).
This looks like a test of two means, but you can also use it to test binary variables (you will need to fill in an SD value with any number).
0.00 <= baseline ES <= 0.05 Satisfies BE
0.05 < baseline ES <= 0.25 with covariates baseline ES > 0.25 Fails
Attrition (Page 10 of https://ies.ed.gov/ncee/wwc/Docs/referenceresources/WWC-Standards-Handbook-v4-1-508.pdf )