Use the following scenario to respond to items 1 - 2:

Do multivitamin supplements improve health? To answer this question, researchers recruited 2000 adults. All were provided with supplies of capsules and were asked to take one capsule per day. One thousand of the adults received capsules that were multivitamin supplements and one thousand received capsules that were a placebo. The researchers used an extensive questionnaire to assess the health of all participants at the start of the study and after two years into the study. Match each number from the outline of the design of this study with the appropriate description.