Question

Use the following information for the question below: You conduct a clinical trial to test whether a new drug relieves the symptoms of arthritis better than a placebo. You have four groups of participants, all of whom have moderately painful arthritis (rated 7 on a scale of 1 to 10). Each group receives a daily pill as follows: group 1-placebo; group 2-15 mg; group 3-25 mg; group 4-50 mg. At the end of 2 weeks, participants in each group are asked to rate their pain on a scale of 1 to 10. What is the independent variable in this experiment?

Answer 1

The independent variable is the dose of the drug given to each participant.

Explanation:

In the current experiment each patient's initial level of pain is going to be the initial condition for the experiment. We're going to measure the final level of pain and we'll try to find any correlation between the variation in the level of pain and the number of milligrams of the drug given to each patient, so that last one (the dose of the drug) is the independent variable because is the one variable that we're going to modify in order to see the effect that it has in the final measurement.