What type of design is characterized by applying a treatment successively to two or more subjects while holding other conditions constant?

The multiple baseline design is particularly effective in scenarios where multiple subjects are involved and allows therapists to observe and compare the effects of a particular intervention across those subjects over time. By applying the treatment successively to each participant while controlling for other variables, this design helps to attribute any observed changes in the subjects directly to the treatment itself.

This approach also enhances the experimental rigor by reducing the risk of confounding variables that could affect the outcomes. The staggered implementation of the treatment across the different subjects allows the clinician to demonstrate the effects of the treatment more convincingly since if the treatment leads to changes in one subject, it can be compared against the others who have not yet received that treatment. The use of a baseline measure prior to treatment is also critical in this design, as it provides a point of comparison to assess the efficacy of the intervention.

In summary, the characteristics of multiple baseline design make it an ideal choice for addressing the effectiveness of music therapy interventions across different clients or subjects while ensuring consistency in conditions.