What is a placebo?

A placebo is defined as a fake drug given to a control group in experiments, particularly in clinical trials. This substance is designed to resemble an active drug but does not contain any therapeutic effect. The purpose of administering a placebo is to serve as a control to compare against the effects of the actual treatment being tested. By providing a control group with a placebo, researchers can more accurately determine the efficacy of the experimental treatment by isolating the psychological effects that might arise from simply being part of a clinical trial, known as the placebo effect.

Understanding the nature of a placebo is crucial in scientific research, as it helps in establishing whether the results observed from a treatment are due to the treatment itself or due to patients' expectations and perceptions. The effectiveness of the active drug can therefore be evaluated based on how it performs compared to the placebo group.