Read FAQs 7.1.1 and 7.1.2 and then answer the following questions:

a. Suppose I want to compare two blood pressure medicines with a paired design. Describe how to carry out the study using repeat observations on each subject.
b. Suppose instead I decide to pair individuals. Do you recommend that I pair subjects by current weight or current height?
c. Which design, the one in (a) or the one in (b), would you recommend? Justify your answer.