A large study used records from Canada's national health care system to compare the effectiveness of two ways to treat prostate disease. The two treatments are traditional surgery and a new method that does not require surgery. The records described many patients whose doctors had chosen one or the other method. The study found that patients treated by the new method were significantly more likely to die within eight years.
You have 300 prostate patients who are willing to serve as subjects in an experiment to compare the two methods.
A.
Assign the nonsurgical treatment to all patients and observe recovery. Then, assign the surgical treatment to the patients who do not recover and again observe recovery.
B.
Ask the patients to select the treatment method they want and divide them into two groups, one group with patients going for surgical treatment and the other group for nonsurgical treatment. Compare the recovery of patients in each group.
C.
Make two groups of 150 patients each by using random assignment. Give the surgical treatment to one group and the nonsurgical treatment to the other group. Observe the recovery of patients in each group.
Answer: C.
Make two groups of 150 patients each by using random assignment. Give the surgical treatment to one group and the nonsurgical treatment to the other group. Observe the recovery of patients in each group.
You have 300 prostate patients who are willing to serve as subjects in an experiment to compare the two methods.
Which of the following statements describes an appropriate design for this randomized comparative experiment?
A.
Assign the nonsurgical treatment to all patients and observe recovery. Then, assign the surgical treatment to the patients who do not recover and again observe recovery.
B.
Ask the patients to select the treatment method they want and divide them into two groups, one group with patients going for surgical treatment and the other group for nonsurgical treatment. Compare the recovery of patients in each group.
C.
Make two groups of 150 patients each by using random assignment. Give the surgical treatment to one group and the nonsurgical treatment to the other group. Observe the recovery of patients in each group.
Answer: C.
Make two groups of 150 patients each by using random assignment. Give the surgical treatment to one group and the nonsurgical treatment to the other group. Observe the recovery of patients in each group.
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