What characterizes a Multiple Baseline Design?

• A. Random assignment of participants
• B. Simultaneous introduction of interventions across all subjects
• C. Staggered introduction of interventions over time
• D. Utilization of control groups to compare results

Answer: (C)

A Multiple Baseline Design is characterized by the staggered introduction of interventions across different subjects, settings, or behaviors. This approach allows researchers to demonstrate the effectiveness of an intervention by observing changes in the behavior of participants as the intervention is gradually introduced over time. By monitoring these changes while controlling for other variables, practitioners can infer that any observed effects are likely related to the intervention rather than to external factors.

The staggered introduction of interventions helps to rule out alternative explanations for behavioral changes and supports causal inferences about the effectiveness of the intervention. Each participant, or "baseline," begins the intervention at different times, which allows for a clear demonstration of the impact of the treatment as the researcher can define the timeline of behavioral change for each individual when the intervention is applied. This design is especially useful in settings where random assignment is not feasible and where it is ethical to withhold an intervention from some participants temporarily.