Question

A research proposal for a medical study describes the following methodology: “The design will involve a placebo-controlled matched-pairs study of the effects of Vitamin D supplements on the frequency of joint pain. The methodological design will control for age, gender, diet, and exercise.”

1. (1 pts) As described above, is this an observational or experimental study?

2. (2 pts) Identify the independent variable/factor being examined in this study.

3. (3 pts) What does the term “placebo controlled” suggest about how the study will be carried out?

Answer 1

a) This is an experimental study , As there are various factors like age, gender, diet and exercise which can be controlled by the investigator and it is used to find the effect of vitamin D supplements on the frequency of joint pain.

b) The independent variable/factor being examined in this study is the frequency of joint pain.

c) The term " Placebo ccntrolled" means that in this study an inactive substance (a placebo) is given to one group of participants, while the vitamin D supplement  being tested is given to another group. The results obtained in the two groups are then compared to see if the Vitamin D supplement  is more effective than the placebo in decreasing the frequency of joint pain