Investigating Hope and Expectations in Open-Label Placebos

Summary

Research has shown that placebo effects contribute substantially to clinical outcomes. Recent evidence suggests that placebos remain effective even if they are openly described as placebos (so-called Open-Label Placebos). In this study, the investigators examine hope and expectations as components of open-label placebos in an experimental study investigating pain..

Conditions

• Pain

Interventions

OTHER

DP

Participants are informed that they are about to receive an effective analgesic cream. They are instructed to apply the cream using a cotton pad.

OTHER

OLP Hope

Participants are informed that they are about to receive an placebo cream. They are told that the cream has no active pharmacological ingredient. Therefore, participants are supposed to evaluate the subjective probability for a positive effect of the cream as rather low. However, using verbal instructions, the investigator aims to induce hope among the participants that the cream could have a positive effect for them because this placebo cream did have a positive among some former participants who were similar to the current participant. The emphasis of this similarity (regarding age and sex) aims to induce a feeling of connectedness to previous participants who reported positive effects of the placebo cream.

OTHER

OLP Expectation

Participants are informed that they are about to receive an placebo cream. They are told that the cream has no active pharmacological ingredient. However, participants are told that placebos have been shown to contribute substantially to clinical outcomes such as pain intensity/unpleasantness. This positive effect of placebos is reasoned by explaining learning mechanisms such as classical conditioning. We anticipated that after hearing this instruction, participants would consider it to be likely that the placebo has a positive effect for them.

OTHER

Placebo cream

The participants receive an inert placebo cream (standard basic cream with oil of thyme produced by a local pharmacy).

OTHER

Heat pain

Participant receive heat pain stimuli using the suprathreshold method of the Thermo Sensory Analyser (TSA-II), a commonly used device to study pain sensation and analgesic effects.

Sponsors & Collaborators

• Philipps University Marburg

  lead OTHER

Principal Investigators

• Tobias Kube, M. Sc. · Philipps University Marburg

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2018-02-10

Primary Completion

2018-06-30

Completion

2018-08-21

Countries

• Germany

Study Locations