A psychologist hypothesizes that the placebo effect is not merely a matter of patient belief but also depends on the warmth and confidence of the practitioner administering the placebo.
Which experimental finding, if true, would most strongly support the psychologist's hypothesis?
- A
Some patients respond strongly to placebos, while others do not.
- B
Placebo effects have been documented in many clinical trials.
- C
Practitioner training varies across clinics.
- Dcheck_circle
Patients given identical placebo treatments by warmer, more confident practitioners reported greater symptom relief than patients given the same placebo by neutral practitioners, with patient belief in the treatment held constant.
Explanation
A holds patient belief constant and varies only practitioner manner, isolating the practitioner's contribution as the psychologist hypothesizes. B, C, and D do not isolate the variable.