Question:

A leading drug company has developed two candidate generic formulations of a therapeutic agent for the treatment of hypertension. In a clinical trial on 18 volunteers, the efficacies of the proprietary product (formulation A) and two generic formulations (formulations B and C) were evaluated. The results presented below represent the blood pressure (systolic) lowering of each formulation in the volunteers.

(b) Describe an appropriate test that may be applied to examine differences between the clinical efficacies of the formulations in the above study (i.e. between formulations A and B, formulations A and C or between formulations B and C). Using this test, examine whether the clinical efficacy of the proprietary formulation differs from the two generic formulations.