06-22-2006, 09:19 AM
In a prospective randomized study comparing drug A to placebo, by the luck of the draw, 80 of the 120 patients assigned to placebo were young and had relatively minor disease severity, whereas 80 of the 120 patients in the group assigned to drug A were older and more severely diseased. The authors report that 95 placebotreated patients and 98 patients treated with drug A are alive at the end of 5 years. They calculate chisquare and report that drug A is no better than placebo. Which of the following statements is true?
(A) Drug A is no more effective than placebo.
(B) Matched pair analysis might demonstrate that drug A is better than placebo.
© Since the patients were assigned by random allocation, it is not possible that the two groups would vary so much in baseline characteristics.
(D) Stratified analysis of the data might demonstrate that drug A is more effective than the placebo.
(E) This is an example of β error
(A) Drug A is no more effective than placebo.
(B) Matched pair analysis might demonstrate that drug A is better than placebo.
© Since the patients were assigned by random allocation, it is not possible that the two groups would vary so much in baseline characteristics.
(D) Stratified analysis of the data might demonstrate that drug A is more effective than the placebo.
(E) This is an example of β error