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?

the drug itself

Explanation:

The independent variable is the variable that changes irrespective of other variables.

When a change in variable is caused due to the change in the independent variable is called the dependent variable.

Here, whether a drug is effective in relieving the symptoms of arthritis is being determined. The drug will be considered effective only if the treatment group show the desired effects. The placebo control group should not show any effects of the drug. Hence, the drug is the independent variable.

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