In a clinical trial for a new pain reliever, half of the volunteers receive the actual drug and the other half receive a sugar pill that is identical in appearance but has no active ingredient. Neither volunteers nor the doctors evaluating them know which pill each volunteer received.
What is the primary purpose of giving the sugar pill (placebo)?
- A
To save money on the experiment
- Bcheck_circle
To create a control group whose response can be compared with the treatment group
- C
To increase the sample size
- D
To reduce variability among subjects
Explanation
A placebo creates a control group that is treated identically except for the active ingredient, allowing the researcher to attribute differences in response to the drug rather than to the act of taking a pill.