ABSTRACT
This chapter introduces a design that will balance out the possible order effects of the drugs. Split–plot designs are useful when the nature of the experiment requires the use of large experimental units for some factors and smaller experimental units for others. A split–plot experiment can be incorporated in other basic designs such as a completely randomized design and a Latin square. The model used for a crossover design depends a great deal on the assumption of carryover effects. Carryover effects are the effects of a treatment that continue into a subsequent time period. Crossover designs are useful for comparing several treatments when subjects use the treatments over two or more periods of time. Screening designs are used in the early stages of a product development to help determine what the levels of the factors should be to yield the "best" product.
