Which design assesses the same subjects multiple times to determine treatment effects?

The approach that assesses the same subjects multiple times to determine treatment effects is known as a repeated measures design. This design allows for the collection of data from the same individuals over different time points or under different conditions, making it particularly useful for tracking changes and understanding how treatments affect those specific subjects over time.

By measuring the same participants repeatedly, researchers can control for individual differences that might otherwise confound the results if different subjects were used in each measurement. This is crucial in music therapy, where personalized response to treatment is often an important focus. Repeated measures designs also increase statistical power because they reduce variability associated with differences between subjects.

In contrast, single subject design focuses on individual cases rather than groups and does not standardly involve multiple measurements across different conditions unless structured as part of a specific intervention. Cross-sectional design gathers data at one point in time and compares different subjects but does not track changes or repeated measures on the same subjects. Neighborhood design, while not a standard term in research design, typically refers to community-related studies and does not pertain to repeated measures of the same subjects. This distinction ensures that repeated measures design stands out as the most suitable choice for evaluating treatment effects through continued observation of the same participants.