To study the effectiveness of a new anti-anxiety drug, researchers randomly assign equally anxious people to two groups, one getting Drug X and the other getting no drug. The researchers mistakenly conclude that Drug X works because people in the drug group show fewer signs of anxiety than the others. What is the mistake?

Question

Quizplus · Accepted Answer

The mistake is not creating a placebo control group. Without a placebo group, it's impossible to determine if the observed effects are due to the drug itself or to psychological factors (e.g., participants believing they are receiving a treatment that will help them).

To Study the Effectiveness of a New Anti-Anxiety Drug, Researchers