ABA and ABAB Designs
Published Online: 30 JAN 2010
Copyright © 2010 John Wiley & Sons, Inc. All rights reserved.
Corsini Encyclopedia of Psychology
How to Cite
Kirk, R. E. 2010. ABA and ABAB Designs. Corsini Encyclopedia of Psychology. 1.
- Published Online: 30 JAN 2010
Single-case designs are often used to assess the effects of an intervention. The designs usually focus on one participant who is observed numerous times. Large-sample designs, by comparison, use many participants who are observed only a few times. The simplest single-case design is the AB design. The letter A denotes a baseline phase during which no intervention is in effect; the letter B denotes the intervention phase. The baseline phase serves three purposes. It provides data about a participant's performance prior to instituting an intervention, it provides a basis for predicting a participant's future performance in the absence of an intervention, and it indicates the normal variability in the participant's performance.