A study is performed to compare several different pain reducing
medications for the treatment of migraine headaches. The drugs
tested are: Placebo, Tylenol, Excedrin, Imitrex. Four hundred
migraine sufferers were recruited for the study and they were
randomly assigned to one of the four groups and were given unmarked
tablets to take when they had a migraine. The effectiveness of pain
relief was documented with a survey and compared between groups.
Which statistical test should be used to compare the pain relief
effectiveness between the four groups?
a. Independent t-test
b. Dependent t-test
c. One way ANOVA
d. Repeated measures ANOVA