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Problem 12 - Entrance Test

In a clinical trial, patients with a certain disease were divided into two groups: Group A received a new experimental drug, and Group B received a placebo (a substance with no medicinal effect). After three months, the recovery rate for each group was recorded. The trial was 'double-blind', meaning neither the patients nor the researchers knew who received the drug or the placebo. What is the primary purpose of including the placebo group (Group B) in this clinical trial?

Correct: B

A placebo group is crucial in clinical trials to account for the 'placebo effect,' where patients experience improvement simply because they believe they are receiving treatment. By comparing the experimental drug group to a placebo group, researchers can determine if any observed effects are genuinely due to the drug's pharmacological action or merely a psychological response. This allows the researchers to 'isolate the effect of the experimental drug' and distinguish it from other factors.