A cardiologist investigated the effect of a selective beta-blocker on the resting heart rate of a group of patients. The resting heart rate, in beats per minute (bpm\text{bpm}bpm), of 18 specific individuals was measured prior to administering the drug, and measured again for the exact same 18 individuals after a two-week course of the medication.
Which of the following is the most appropriate procedure for the statistical analysis of these data?
Calculate the mean resting heart rate before and after the treatment, and use a paired ttt-test.
Calculate the mean resting heart rate before and after the treatment, and use an unpaired ttt-test.
Calculate the median resting heart rate before and after the treatment, and use a Spearman's rank correlation coefficient.
Calculate the median resting heart rate before and after the treatment, and use a chi-squared test.
