ABSTRACT
A repeated measures design deals with response outcomes measured on the same experimental unit at different times or under different conditions. Repeated measurements can refer to multiple measurements on an experimental unit, such as the measurements of thickness of skin in arms, hands, fingers, face, neck, and trunk of scleroderma patients. Repeated measurements can be taken over a period of time, such as daily measurements of blood glucose levels or weekly measurements of systolic blood pressures or weights. The repeated assessments might be measured under different experimental conditions. Collecting repeated measurements can provide a more definitive evaluation of within-subject change across time. Moreover, collecting repeated measurements can simultaneously increase statistical power for detecting changes while reducing the costs of conducting a study. The repeated measurement design is generally more efficient for determining a treatment effect than completely randomized designs [1].
