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 are the explanatory and response variables in this experiment?(b) Outline the design of the experiment. Use your judgment in choosing the group sizes.(c) The study was double-blind. What does this mean?(d) What does "no significant difference" mean in describing the outcome of the study?(e) Suggest some lurking variables that could explain why people who eat lots of fruits and vegetables have lower rates of colon cancer. The experiment suggests that these variables, rather than the antioxidants, may be responsible for the observed benefits of fruits and vegetables.

Answer 1

Explanation:

(a). The explanatory variables are the antioxidant group, the response variable is the result of the rate of colon cancer

(b)The design of the experiment is stratified Random sampling. I'll suggest there divided into equal group of 216 each.

(c). Double blind is when the people subjected to the experiment are not in the know if they're given placebo or the real antioxidant

(d) No significant difference mean, there is no convincing relationship that those that engage in using antioxidant have reduced colon cancer rate.

(e) Awareness of its history in family, age also.