Traeger and Kamper4 also raise the question of whether participants were given a psychological intervention aimed at boosting expectations of a positive outcome. We tend to agree that this boosting of expectations for a positive outcome can be considered a psychological intervention. However, it is important to note that all medical interventions include this “psychological intervention” conveyed in the way the physician prescribes the treatment and explains the expected results. This phenomenon is the reason for placebo control groups in randomized clinical trials. In our study, the information given to participants was rigorously controlled, and all participants received the same information in the same warm and empathetic context, regardless the condition to which they were assigned, ie, with and without the placebo pills. Nevertheless, we found significant differences between conditions, with a 30% improvement in pain and pain-related disability in the placebo group.
We agree that the phrase placebo effect is an oxymoron: “the effect of an inert substance.” There have been many attempts to find a new term; none have successfully conveyed the idea to the medical community as well as “placebo effect.”2 We look forward to hearing Traeger and Kamper's as well as others' suggestions for a better term that could be adopted and widely used.
We also would have liked to include mechanistic questions as part of the study. But our primary aim was to pilot a new way to harness placebo effects in clinical practice. Given our resources that is what we focused on.
Finally, we acknowledge Traeger and Kamper's recommendation4 for studies to account for the testing of the mechanisms of active and inactive interventions. Previous research3 on elements of placebo response has shown that nonspecific effects can produce statistically and clinically significant outcomes and that the patient–practitioner relationship is the most robust component of placebo.