Placebos in Healthcare: A Behavioral Study on How Treatment Responsiveness Affects Therapy Decisions in a Simulated Patient-Physician Interaction

Abstract

Background and purpose: Treatment choice during clinical practice is crucial to best help each patient. One of the physicians' main goals is choosing a personalized effective treatment, but it also represents a challenging issue. Here, we explored different treatment choices in a simulated patient-physician interaction.

Materials and methods: Medical students (n = 48) and young Practicing Physicians (n = 20) were recruited to behave as "physicians" while fellow researchers acted as "patients". Participants were divided equally into a Belief Group, which received positive information about placebo efficacy, and a Non-Belief Group, which received negative information. Empathy traits and psychological variables were measured in both groups. During the task, participants were asked to choose between an active (TENS treatment) or a placebo treatment, to reduce patients' pain. Patients never underwent the painful stimulation but acted as if they had, simulating high or low pain responses to the placebo treatment (placebo-responders/placebo non-responders) and low pain to the TENS treatment.

Results: Behavioral results showed that the Belief Group gave significantly more placebo treatments when faced with a patient that simulated placebo responsiveness, while the Non-Belief group showed a mirrorlike behavior, administrating more believed TENS treatments when faced with a placebo non-responder. No differences were found between Medical Students and Practicing Physicians.

Conclusions: This study constitutes a frame of reference for medical treatment decisions, indicating that physicians' treatment choices are influenced by patients' responsiveness to the treatments, as well as by their prior beliefs and empathy traits.

Keywords: empathy; general practice; physician–patient relationship; placebo effect; placebos; treatment outcome.

Figure 1

Experimental paradigm. Experimental timeline and representation of the experimental groups.

Figure 2

Belief Group results. Participants in the Belief Group (Medical Students and Practicing Physicians) administered significantly more placebo treatments in comparison with the believed TENS treatments when faced with placebo responsiveness; participants in the Belief Group (Medical Students and Practicing Physicians) administered significantly more placebo treatments when the patient was a placebo responder than when they were a non-responder. Error bars represent the standard error of the mean (SEM); ** p < 0.01.

Figure 3

Non-Belief Group results. Participants in the Non-Belief Group (Medical Students and Practicing Physicians) administered significantly more believed TENS treatments than placebos when faced with placebo non-responders; participants in the Non-Belief Group (Medical Students and Practicing Physicians) administered significantly more believed TENS treatments when the patient was a placebo non-responder, than when they were a responder. Error bars represent the standard error of the mean (SEM); * p < 0.05, ** p < 0.01.

Figure 4

Significant correlations. (A) Positive correlation between JSPE scores (x-Axis) and number of placebos administered (y-Axis) in the Belief Group, both for the Medical Students (r = 0.85, p < 0.001) and for the Practicing Physicians (r = 0.87, p < 0.01); (B) negative correlation (r = 0.67, p < 0.001) between JSPE scores (x Axis) and number of placebos administered (y Axis) in the Non-Belief Group, both for the Medical Students (r = −0.67, p < 0.001) and for the Practicing Physicians (r = −0.78, p < 0.01).