Question

People who eat lots of fruits and vegetables have lower rates of colon cancer than those who eat little of these foods. Fruits and vegetables are rich in "antioxidants" such as vitamins A, C, and E. Will taking antioxidants help prevent colon cancer? A medical experiment studied this question with 864 people who were at risk of colon cancer. The subjects were divided into four groups: daily beta-carotene, daily vitamins C and E, all three vitamins every day, or daily placebo. After four years, the researchers were surprised to find no significant difference in colon cancer among the groups. (a) What is the treatment and response in this experiment? Treatment type of food (fruit and vegetables or neither) at risk or not of colon cancer whether or not subjects consumed beta-carotene, vitamins C and E or both each day whether or not colon cancer develops Response at risk or not of colon cancer whether or not colon cancer develops type of food (fruit and vegetables or neither) O whether or not subjects consumed beta-carotene, vitamins C and E or both each day (b) Outline the design of the experiment. Use your judgment in choosing the group sizes. (Select all that apply.) Randomly assign subjects to 4 treatments. Observe eating habits. Randomly assign 2 treatments to 4 groups. Observe the occurrence of colon cancer. Randomly assign subjects to 2 treatments. (c) The study was double-blind. What do you suppose this means? Only blind subjects were used to avoid confounding of sight. The researchers who examined the subjects did not know which subject got which treatment. The subject did not know which treatment they were receiving. Neither the subjects nor the researchers who examined them knew who was getting which treatment. N . ... _. . :. -L. . - -- - - .. .... . . . . .... ... . ... ...... . ....:
Solve for part b and e