Investigating Hope and Expectations in Open-Label Placebos

Not Applicable

Completed

• Conditions: Pain

• Registration Number: NCT03517644
• Lead Sponsor: Philipps University Marburg Medical Center

Brief 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..

Detailed Description

A growing body of research has indicated that placebos contribute substantially to clinical outcomes. Yet, the implementation of deceptive placebos in clinical practice is incompatible with key principles of openness and patient autonomy. However, recent research suggests that placebos remain effective even if they openly described as placebos (so-called Open-Label Placebos (OLP)), hence questioning the necessity of deception in clinical trials. However, research identifying the specific mechanisms underlying OLP is lacking. Therefore, the current study aims to examine hope and expectations as components of OLP in pain.

For this purpose, experimentally induced heat pain is examined. First, all participants receive heat pain stimuli and evaluate them. Next, participants are randomly assigned to one of four groups: (1) a traditional deceptive placebo (DP) group, which is told that they receive an effective analgesic cream, (2) an OLP group inducing hope among the participants that the placebo cream could help them tolerating painful stimuli (OLP hope), (3) and OLP group raising the expectation that the placebo cream will help participants tolerating heat pain (OLP expectation), (4) a control group receiving no cream. Finally, participants receive and evaluate heat pain again.

Study Timeline

• Study Start: 2018-02-10
• Study First Submitted: 2018-03-07
• Study First Submitted QC: 2018-04-24
• Study First Posted: 2018-05-07
• Primary Completion: 2018-06-30
• Status Verified: 2018-08
• Study Completion: 2018-08-21
• Last Update Submitted: 2018-08-22
• Last Update Posted: 2018-08-23

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

• sufficient German language knowledge
• at least 18 years old

Exclusion Criteria

• current mental disorder
• current medical disease
• studying psychology or medicine
• pregnancy or breastfeeding period
• intake of drugs
• severely visually impaired

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in pain intensity scale	Baseline and 45 minutes	Change in subjective pain intensity assessed using a visual analogue scale (ranging from 0 to 100, with higher values reflecting more pain intensity)

Secondary Outcome Measures

Name	Time	Method
Change in pain unpleasantness scale	Baseline and 45 minutes	Change in subjective pain unpleasantness assessed using a visual analogue scale (ranging from 0 to 100, with higher values reflecting more pain unpleasantness)
Change in physiological heat pain threshold	Baseline and 45 minutes	Change in the individual heat pain threshold (the point when the stimulus changes from being warm to being painful)
Change in physiological heat pain tolerance	Baseline and 45 minutes	Change in the individual heat pain tolerance (the point when participants cannot stand the heat pain stimulus any longer)

Trial Locations

Locations (1)

Philipps-University of Marburg; 🇩🇪 Marburg, Hessen, Germany