Which design withdraws the intervention and reintroduces it to demonstrate replication of effects?

• A. ABAB Design
• B. Reversal design
• C. Antecedent
• D. Anecdotal Observation

Answer: (A)

This design tests whether an intervention truly causes a change by withdrawing and then reintroducing it to show the effect replicates. In this approach, you start with a baseline, apply the intervention, return to baseline, and then apply the intervention again. If the behavior shifts in the same direction during both intervention phases and returns toward baseline when the intervention is withdrawn, you have replication of effects that supports a functional relation between the intervention and the behavior.

While a reversal design in general involves withdrawing and reintroducing conditions, the ABAB form explicitly repeats the reversal to demonstrate replication across phases, strengthening the inference that the intervention drives the change. The other options don’t describe a design that uses repeated withdrawal and reintroduction to establish replication: an antecedent is just a triggering event, and anecdotal observation is a non-systematic data collection method.