Hypoalgesic placebo effects can occur with transparent disclosures
Placebo research often involves elements of deception to create expectations of benefit. Typically, it consists in deliberate misleading communication about the goal of the research and the nature of the experimental manipulation and treatment. Specifically, in the context of placebo pain-related research, misleading information is used to make participants believe that certain procedures (eg, placebo creams, saline solution injections, sham electrodes, and so on) can induce a reduction in pain they experience. Study participants can be informed about the use of deception (ie, authorized deception) during the informed consent process and then at the end of their participation in the study during the debriefing phase (eg, Ref. 2), told about the true nature of research and the features of the protocol making the research ethically sound.