Which design allows for observing behaviors across stages of treatment and no treatment?

The repeated measures design is effective in observing behaviors across different stages of treatment as it involves assessing the same subjects at multiple points in time. This enables the therapist to capture changes in behavior that occur as a result of therapeutic interventions and to compare these changes to observations made at times when no treatment is being administered. By evaluating the same individuals throughout various phases, including baseline (no treatment) and treatment periods, this design provides clear insights about the effects of the intervention.

This design's strength lies in its ability to track progress within the same subjects, minimizing variability that could be introduced by different participants, making it easier to infer the effectiveness of the treatment. This is crucial in music therapy, where individuals may respond differently to various stages of treatment, and being able to observe these changes over time can provide valuable information for clinical decisions.

Other designs, such as random group or matched pairs, focus more on comparing different groups rather than the same individuals at various treatment stages. The multiple baseline design, while effective in its own right, does not necessarily involve observing through multiple treatment phases in the same way that a repeated measures design does.