Question

You are going to conduct an experiment to determine which of four brands of dog food promotes growth best in puppies ages four months to one year. You are concerned that the effect might vary by the breed of dog, so you divide the dogs into five different categories of breed. This gives you eight dogs in each category. You randomly assign two of the dogs in each category to one of the four foods. The design of this study is best described as:

Answer 1

A. Randomized block, blocked by breed of dog
B. Randomized block, blocked by type of dog food
C. Matched pairs, with each two dogs considered a pair
D. A controlled design in which the various breed of dogs are the controls
E. Randomized block, blocked by breed of dog and type of dog food