Quit smoking: the new england journal of medicine published the results of a double-blind, placebo-controlled experiment to study the effect of nicotine patches and the antidepressant bupropion on quitting smoking.
with the data from the experiment we calculate the sample difference in the "quit smoking" rates for the nicotine treatment group and the placebo group ("treatment" minus "placebo"). we get 0.8% = 0.008. the 99% confidence interval based on this sample difference is -0.1036 to 0.0882.
which of the following is a valid conclusion?
we are 99% confident that the proportion of smokers who will quit smoking with a nicotine patch treatment is about 8.8 to 10.4% higher than the proportion who quit smoking with a placebo treatment.
the nicotine patch treatment is not effective in smokers quit. we are 99% confident that smokers using a nicotine patch treatment have a "quit smoking" rate that is anywhere from 10.4% lower to 8.8% higher than the success rate of smokers with a placebo treatment.