Investigating Hope and Expectations in Open-Label Placebos

NCT03517644 | Completed

• 1 other identifier: 2017-58v
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

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..

Conditions

Pain

Outcome Measures

Primary Outcomes (1)

• Change in pain intensity scale

  Change in subjective pain intensity assessed using a visual analogue scale (ranging from 0 to 100, with higher values reflecting more pain intensity)

  Baseline and 45 minutes

Secondary Outcomes (3)

• Change in pain unpleasantness scale

  Baseline and 45 minutes

• Change in physiological heat pain threshold

  Baseline and 45 minutes

• Change in physiological heat pain tolerance

  Baseline and 45 minutes

Study Arms (4)

Deceptive Placebo (DP)

EXPERIMENTAL

After pretreatment heat pain assessment, participants are informed that they are about to receive an effective analgesic cream. In fact, they receive a placebo cream. Next, the posttreatment pain assessment is conducted.

Other: DP; Other: Placebo cream; Other: Heat pain

OLP with Hope (OLP Hope)

EXPERIMENTAL

After pretreatment heat pain assessment, participants are informed that they are about to receive an placebo cream. They are told that the cream has no active pharmacological ingredient. However, using verbal instructions, the investigator aims to induce hope among the participants that the cream could have a positive effect. Next, the posttreatment pain assessment is conducted.

Other: OLP Hope; Other: Placebo cream; Other: Heat pain

OLP with Expectations (OLP Expectation)

EXPERIMENTAL

After pretreatment heat pain assessment, participants are informed that they are about to receive an placebo cream. They are told that the cream has no active pharmacological ingredient. However, using verbal instructions, the investigator aims to raise expectations among the participants that the cream will have a positive effect. Next, the posttreatment pain assessment is conducted.

Other: OLP Expectation; Other: Placebo cream; Other: Heat pain

Control

EXPERIMENTAL

After pretreatment heat pain assessment, this group does not receive an intervention targeting pain sensation prior to the posttreatment pain assessment.

Other: Heat pain

Interventions

DP OTHER

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

Deceptive Placebo (DP)

OLP Hope OTHER

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.

OLP with Hope (OLP Hope)

OLP Expectation OTHER

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.

OLP with Expectations (OLP Expectation)

Placebo cream OTHER

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

Deceptive Placebo (DP); OLP with Expectations (OLP Expectation); OLP with Hope (OLP Hope)

Heat pain OTHER

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.

Control; Deceptive Placebo (DP); OLP with Expectations (OLP Expectation); OLP with Hope (OLP Hope)

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• sufficient German language knowledge
• at least 18 years old

You may not qualify if:

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

Sponsors & Collaborators

• Philipps University Marburg: lead

Study Sites (1)

Philipps-University of Marburg

Marburg, Hesse, 35037, Germany

Location

MeSH Terms

Conditions

Pain

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Tobias Kube, M. Sc.

  Philipps University Marburg

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Using a cover story, participants are instructed to think that there are three experimental groups: a treatment condition, a placebo condition, and a control condition. Therefore, participants from the open-label groups do know that they receive a placebo, but do not know which specific mechanism is being addressed in their condition.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Participants are assigned to one of four experimental groups in parallel for the duration of the study

Study Record Dates

• First Submitted: March 7, 2018
• First Posted: May 7, 2018
• Study Start: February 10, 2018
• Primary Completion: June 30, 2018
• Study Completion: August 21, 2018
• Last Updated: August 23, 2018

Record last verified: 2018-08

Data Sharing

• IPD Sharing: Will not share

Locations

DE (1)