Concept explainers
Treatment for Osteoporosis Osteoporosis is a condition in which people experience decreased bone mass and an increase in the risk of bone fracture. Actonel is a drug that helps combat osteoporosis in postmenopausal women. In clinical trials, 1374 postmenopausal women were randomly divided into experimental and control groups. The subjects in the experimental group were administered 5 milligrams (mg) of Actonel, while the subjects in the control group were administered a placebo. The number of women who experienced a bone fracture over the course of one year was recorded. Of the 696 women in the experimental group, 27 experienced a fracture during the course of the year. Of the 678 women in the control group, 49 experienced a fracture during the course of the year.
- a. What type of experimental design is this? What is the response variable? Is it qualitative or quantitative? What are the treatments?
- b. The experiment was double-blind. What does this mean?
- c. Does the sample evidence suggest the drug is effective in preventing bone fractures? Use the α = 0.01 level of significance.
- d. Construct a 95% confidence interval for the difference between the two population proportions, pexp − pcontrol.
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Fundamentals of Statistics (5th Edition)
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