a setup for experiments requiring the measurement of the dependent variable prior to onset of the experiment and again after it.

A-B DESIGN: "The A-B Design is one of the most commonly used experimental designs as it is the most basic and generally the first experimental design people learn academically, though they may not know it by this name at the time."
Cite this page: Nugent, Pam M.S., "A-B DESIGN," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/a-b-design/ (accessed June 25, 2017).