Dr.Baxter conducts an experiment investigating the effectiveness of a new antacid on reducing stomach pain.He recruits 100 chronic sufferers of acid indigestion,and places them in four groups,each receiving a different amount of medication.The first group receives a sham pill because it contains none of the new antacid whatsoever.He is very surprised,however,when he finds that group one reports a statistically significant reduction in stomach pain after taking their pill.Which of the following best explains why the participants in group one showed a response to the pill,even when it had no active ingredient?
A) The subject-expectancy effect
B) Demand characteristics
C) The placebo effect
D) The observer-expectancy effect

Question

Quizplus · Accepted Answer

The participants in group one showed a response to the pill because of the placebo effect. The placebo effect is the phenomenon where a person experiences a positive response to a treatment, even though it contains no active ingredients. This effect is believed to be due to the person's belief and expectation that the treatment will be effective. In this case, the participants in group one may have believed that the pill contained the new antacid, and their expectation of its effectiveness may have led to a reduction in their stomach pain.

DrBaxter Conducts an Experiment Investigating the Effectiveness of a New