Back to Basics - Effects, Narratives and Routes of Administration of Open-label Placebo
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Enrollment
- 160
- Locations
- 2
- Primary Endpoint
- subjective intensity and unpleasantness ratings of heat pain tolerance
Study Overview
Brief Summary
To date, very little is known about the mechanisms of open-label placebo treatment and there is a lack in highly controlled experimental designs. Therefore, the planned project will test well-established explanatory models of (deceptive) placebo, i.e., (1) expectancy, (2) meaning response, in an open-label placebo design, investigating their influence on placebo analgesia.
Detailed Description
The current project will consist of one experimental study and one qualitative study:
- the effects of open-label, and deceptive placebo administration on placebo analgesia will be directly compared when both groups have a comparable expectancy-inducing scientific rationale;
- subjective meaning models will be assessed by comparing subjective narratives of the placebo effect in open-label and deceptive placebo groups in a nested qualitative study.
The experimental study will be a randomized experiment with healthy subjects (N=120), and pain will be induced using a standardized heat pain paradigm (Medoc, Ramatishai, Israel; thermo-sensory analyzer (TSA)-II). Effects of the experimental conditions will be assessed both objectively (i.e. heat pain threshold and tolerance) and subjectively (i.e. subjective pain ratings, pain intensity and unpleasantness). Furthermore, investigators will randomly select 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, as well as in the control group.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Basic Science
- Masking
- Single (Participant)
Eligibility Criteria
- Ages
- 18 Years to 65 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Healthy male and female adults aged 18-65
- •Healthy by self-report statement, thus no known current or chronic somatic diseases or psychiatric disorders
- •Right-handedness (Oldfield, 1971),
- •Willing to participate in study
Exclusion Criteria
- •Medicine or Psychology Students
- •Any acute or chronic disease (chronic pain, hypertension, heart disease, renal disease, liver disease, diabetes) as well as skin pathologies, neuropathies or nerve entrapment symptoms, sensory abnormalities affecting the tactile or thermal modality
- •Current medications (psychoactive medication, narcotics, intake of analgesics) or being currently in psychological or psychiatric treatment
- •Insufficient German language skills to understand the instructions
- •Previous participation in studies using pain assessment (threshold and tolerance) with Peltier Devices
- •Daily consumption of more than three alcoholic standard beverages per day (a standard alcoholic beverage is defined as either 3dl beer or 1 dl wine or 2cl spirits)
- •Current or regular drug consumption (THC, cocaine, heroin, etc.)
Arms & Interventions
open-label placebo
Participants (N=40) will have the information that they are receiving an inert cream (i.e. "placebo"). Placebo will be described as an inert or inactive cream, with no medication in it. Additionally, participants will be told that "placebo has been shown in rigorous clinical testing to produce significant mind-body self-healing processes." The placebo administration will be combined with the following scientific rationale/verbal suggestion: (a) placebos are effective analgesics, (b) classical conditioning as a possible mechanism of this effect, (c) compliance is important for outcome and (d) positive expectations increase placebo effects, but are not necessary.
Intervention: open-label placebo (Other)
deceptive placebo
Participants (N=40) will have the information that they are receiving an analgesic cream ("Antidolor, containing "Lidocain"), while in fact they will receive an inert cream, only. Antidolor will be described as an analgesic cream.
Intervention: deceptive placebo (Other)
control group
Participants (N=40) will have the information that they are receiving an inert control cream.
Intervention: open-label placebo (Other)
no treatment group
Participants (N=40) will be told that they are in the "no treatment group" and that they will not receive an analgesic cream.
Outcomes
Primary Outcomes
subjective intensity and unpleasantness ratings of heat pain tolerance
Time Frame: 2 hours
Visual Analogue Scale (VAS)
objective heat pain tolerance
Time Frame: 2 hours
Temperatures
Secondary Outcomes
- Desire for Relief Scale (DRS)(2 hours)
- subjective intensity and unpleasantness ratings of heat pain threshold(2 hours)
- objective heat pain threshold(2 hours)
- multidimensional sensitivities questionnaire (Mehrdimensionaler Befindlichkeitsfragebogen (MDBF))(2 hours)
- NEO five-factor inventory (NEO-FFI)(2 hours)
- Credibility and Effectiveness of the placebo analgesia expectation; adapted Version of the Context Model Questionnaire; Kontextmodellfragebogen (KMF)(2 hours)
- Revised Life Orientation Test (LOT-R)(2 hours)
- questionnaire on competence and locus of control (Fragebogen zu Kompetenz- und Kontrollüberzeugungen (FKK))(2 hours)
- Expectancy of Relief Scale (ERS; Erwartungsfragebogen)(2 hours)
- Anxiety and Depression Scale (HADS-D)(2 hours)
- Beliefs in holistic health and holistic treatments; Complementary and Alternative Medicine Beliefs Intentory (CAMBI)(2 hours)
- sociodemographic questionnaire (Soziodemographischer Fragebogen (SDD))(2 hours)