Back to Basics - Effects, Narratives and Routes of Administration of Open-label Placebo

The study aimed to test established explanatory models of placebo in an open-label placebo design with healthy participants (N=160) in a standardized experimental heat pain paradigm. In the main study, we aimed to analyze (1.) if open-label placebo administration has comparable effects on placebo analgesia as a deceptive placebo administration when expectancy is induced using a scientific rationale in both groups. We therefore set out to examine the effects of open-label placebos in a standardized heat pain experiment with healthy participants. We compared open-label placebo administration with a rationale (OPR+) and without a rationale (OPR-) to deceptive placebo (DP) administration and a no treatment (NT). Subsequently (2.), we randomly selected 30 participants to take part in a nested qualitative study in order to qualitatively assess the meaning response by comparing subjective narratives of the placebo effect in the open-label and deceptive placebo groups.