Question

Artery disease. An article in the New England Journal of Medicine describes a randomized controlled trial that compared the effects of using a balloon with a special coating in angioplasty (the repair of blood vessels) compared with a standard balloon. According to the article, the study was designed to have power 90%, with a two-sided Type I error of 0.05, to detect a clinically important difference of approximately 17 percentage points in the presence of certain lesions 12 months after surgery.13 What fixed significance level was used in calculating the power? Explain to someone who knows no statistics why power 90% means that the experiment would probably have been significant if there was a difference between the use of the balloon with a special coating compared to the use of the standard balloon.

Answer 1

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Step-by-step explanation:

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