Question

A nutritionist wanted to determine which of two behaviors would give people the most energy. She selected a sample of 50 adult participants. For one month, the participants were asked to exercise for 30 minutes per day. For another month, they drank an energy drink every day. The order of the treatments was assigned to the participants at random. The participants were asked to record each day when they completed their treatment and to rate their energy level that day on a scale of 1–10. After the two months of treatments, the nutritionist collected the data and calculated and compared the mean change (exercise – energy drink) in energy level for all 50 participants. What type of experimental design did the nutritionist use?

1) Randomized block experimental design
2) Completely randomized experimental design
3) Matched pairs experimental design
4) None (observational study only)

Answer 1

It's c

Step-by-step explanation:

I just did it

Answer 2

The nutritionist used a matched pairs experimental design, where each participant received both treatments, and comparisons were made within individuals.

Step-by-step explanation:

The experimental design used by the nutritionist is a matched pairs experimental design. In this approach, each participant acts as their own control by undergoing both treatments, with the order of treatments being assigned at random. The participants' energy levels are compared within individuals for each treatment rather than between different individuals, thus controlling for individual differences. This design is ideal for experiments where each participant can receive both treatments, and it effectively deals with potential variability among participants that could affect the outcome.