1 In clincial trials of the headache drug Zocor some subject

1. In clincial trials of the headache drug Zocor, some subjects were treated with Zocor and others were given a placebo (a sugar pill). The 95% confidence interval for the difference between the proportion of subjects who experienced headaches is -.0518

Solution

Interpretation of Confidence Interval:

We can say with 95% confidence that difference between the proportion of people given Zocor and proportion of people given placebo experienced headache is less than -0,0194 and greater than -0.0518