Which design involves rapid alternation of two treatments across phases to compare their effects?

• A. ABAB Design
• B. A-B-A design
• C. Alternating Treatment Design
• D. Antecedent

Answer: (C)

The design being described is a method that compares two treatments by switching between them rapidly across sessions, so you can see which one produces the desired effect within the same individual and setting. In this approach, each treatment is applied in brief, alternating segments, often with random order to reduce sequence effects. This direct, within-subject comparison makes it possible to attribute differences in behavior to the treatments themselves rather than to time or other outside factors. Unlike reversal designs that involve withdrawing or reinstating a treatment to demonstrate control, this design focuses on rapid alternation to contrast the treatments side by side. The option referring to antecedents isn’t a design at all in this context.