In an experimental study evaluating the effectiveness of an antidepressant medication, one group of participants receives a sugar pill instead of the true medication. This is an example of a:

A) medication-withdrawal study.
B) symptom-exacerbation study.
C) multiple-baseline study.
D) placebo study.

Placebo Study

Research that investigates the effect of a treatment by comparing the response of subjects receiving an inactive substance or sham treatment to those receiving the actual treatment.

Sugar Pill

A placebo used in clinical trials to test the efficacy of medications, which has no therapeutic effect but can influence participants' perceptions of their symptoms.

Antidepressant Medication

A class of drugs designed to improve symptoms of depression by altering chemical imbalances of neurotransmitters in the brain.