Can the Open Label Placebo Rationale Be Optimized?

If only they knew! A non-inferiority randomized controlled trial comparing deceptive and open-label placebo in healthy individuals

BACKGROUND

Placebo use is widespread in clinical practice. However, they are most often administered deceptively rather than openly. It is often suggested that open-label placebos (OLP) are less effective than deceptive placebos (DP). This study aimed to compare the use of DP and OLP treatments to reduce pain in healthy volunteers.

METHODS

We conducted a non-inferiority, parallel, randomized, controlled trial, which also included a nested cross-over no-treatment condition. This study was conducted at a university clinic in France.

RESULTS

We included 60 subjects and the main result shows that the OLP was not inferior to the DP by a margin of 10 mm. The mean difference between both groups regarding intensity of pain was 0.7 mm with a 95% compatibility interval (95% CI) of ]-∞; 5.4], and 97.5% CI of ]-∞; 6.3]. Secondary outcomes require cautious interpretation of the effect of placebo versus no treatment due to a time-treatment interaction.

CONCLUSION

The study indicates that OLP may perform just as well as DP and could provide support for the use of OLP as an ethical alternative to DP when they are to be used in a clinical setting. If only patients knew about the placebo nature of some treatments they are receiving, unnecessary lies could be avoided while maintaining similar placebo effects.

SIGNIFICANCE

This study is the first to show non-inferiority of placebos administered honestly, also called OLP, compared to DP in reducing pain. This suggests that OLP could be as effective as their deceptive counterparts while having the ethical advantage of not being required to lie. If deception is not a necessary condition for efficacy, OLP should be preferred over DP.

‘It's not my greengrocer, it's someone from the medical profession’: A qualitative study regarding acceptability of deceptive and open‐label placebo prescribing in France

OBJECTIVES

To explore participants' views regarding clinical use of deceptive placebo (DP) and open-label placebo (OLP) treatments.

DESIGN

Qualitative thematic analysis.

METHODS

We conducted eight semi-structured interviews with healthy participants in an experimental trial comparing the efficacy of OLP and DP (Clinical trials n°NCT03934138). Interviewees' opinions were solicited following administration of placebos during the trial. Interviews were analysed using data-driven analysis.

RESULTS

We identified three themes. First, participants considered trust central in judging a placebo treatment to be acceptable. They expressed the importance of an implicit trust both in their health care professionals' (HCPs') competency as well as in the profession at large. A second theme was the perception of how placebo treatments might solve health problems. Acceptability of both types of placebo treatments was dependent on the perception patients had about the treatment solving their problem and/or doubts regarding the effectiveness of placebos The third theme encompassed perceived risks associated with placebo prescribing. Some comments viewed placebos positively as facilitating reduced medication intake. However, participants also identified the potential of placebos to generate adverse side effects.

CONCLUSIONS

Treatment acceptability by patients is a pre-requisite, alongside effectiveness, to harness OLPs in clinical care. Our study identified the importance of trust in HCPs prescribing placebos, the clinical effectiveness of placebos and the potential risks of these interventions in assessing their acceptability. Future research is needed to explore the contexts in which placebos might be used, and how best to communicate information about placebo interventions.