What is the focus of a multiple baseline design?

A multiple baseline design is primarily focused on evaluating the effect of an intervention by sequentially introducing it across multiple subjects, behaviors, or settings while monitoring the outcomes. This approach allows researchers and practitioners to observe the impact of treatment over time within individual cases rather than relying on random assignment or a single time frame.

By systematically applying the treatment to one subject or aspect at a time and continuing to collect data for the others, the design effectively demonstrates that any observed changes in behavior can be attributed to the treatment rather than other factors. This is particularly useful in settings where waiting for a control group to receive treatment is impractical or unethical.

The other options do not frame the essence of a multiple baseline design correctly. Observing behaviors prior to and after treatment typically represents a pre- and post-intervention analysis but does not convey the sequential nature of treatment application that defines the multiple baseline strategy. Random assignment pertains more closely to experimental designs rather than observational frameworks like multiple baselines, which do not rely on random grouping. Assessing behaviors at various times without treatment could describe a different kind of observational study but lacks the structured approach of implementing treatment across subjects or settings incrementally.