Evaluation Glossary

Ex-post Facto Design

A research design in which all group selection, pretest data, and post-test data are collected after completion of the treatment. The evaluator is thus not involved in the selection or placement of individuals into comparison or control groups. All evaluation decisions are made retrospectively.


US Environmental Protection Agency. (2007). Program Evaluation Glossary. Office of the Administrator/Office of Policy/Office of Strategic Environmental Management/Evaluation Support Division.

Related Terms

After-Only Designs
Ex-post Evaluation
One-shot Case Study
Post-test Only Design