In a test of the effectiveness of acupuncture in treating migraine headaches, a random sample of patients at a migraine clinic were provided with a...

1.In a test of the effectiveness of acupuncture in treating migraine headaches, a random sample of patients at a migraine clinic were provided with a novel acupuncture treatment daily for 6 months. The patients were interviewed at the start of the study and at the end to determine whether there had been any change in the severity of their migraines. Which of the following would you suggest to improve the experimental design the most? (Select the BEST answer)