I'm doing research on the influence of one kind of pill on the heart rate. I have two groups: control group and medication group. The control group has 10 subjects while the medication group has 20 different subjects.
Firstly, all 30 subjects' heart rate data were recorded every 15 seconds. Then, the subjects in control group were given a kind of placebo and the subjects in medication group were given pills (they didn't know whether they were given pills or placebo). After that, the heart rate were recorded again every 15 seconds.
In case the description is too complicated, I attached a plot to intuitively show the design, in which the real data were replaced with "xxx".
Now I want to test whether the heart rate of medication group is statistically different from that of control group. What kind of test should I use? Can I use hierarchical ANOVA?