Phil is a participant in a study designed to examine the effects of taking a dietary supplement on muscle tissue development.Phil suspects he is in the experimental group,because he is certain his muscles are bigger and stronger as a result of taking the product supplied by the researchers.When the study is completed,Phil learns that he did not receive the dietary supplement.Phil thinks the researchers made a mistake-he is certain his muscle mass increased while he took the supplement.According to this information,Phil's belief that his physical condition improved while he participated in the study is an example of ________.
A)the placebo effect
B)an anecdotal report
C)human subject bias
D)participant fatigue

Question

Quizplus · Accepted Answer

Phil's belief that his physical condition improved while he participated in the study, despite not actually receiving the dietary supplement, is an example of the placebo effect. The placebo effect occurs when participants in a study experience changes in their condition, either positive or negative, as a result of their beliefs or expectations about the treatment, rather than the treatment itself. In this case, Phil believed he was receiving a supplement that would improve his muscle mass, and his belief alone may have led to changes in his muscle tissue.

Phil Is a Participant in a Study Designed to Examine