Clinical trial NCT02578420: Back to Basics - Effects, Narratives and Routes of Administration of Open-label Placebo
Official title: Back to Basics - Effects, Narratives and Routes of Administration of Open-label Placebo
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Placebo Effect
Pain
Expectancy
Lead sponsor: University Hospital, Basel, Switzerland
Sponsor class: OTHER
First posted: 2015-10-19
Enrollment: 160
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

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:

1. 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;
2. 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.

Eligibility criteria: 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.)

Primary outcomes:
measure: subjective intensity and unpleasantness ratings of heat pain tolerance
timeFrame: 2 hours
measure: objective heat pain tolerance
timeFrame: 2 hours
Secondary outcomes:
measure: Expectancy of Relief Scale (ERS; Erwartungsfragebogen)
timeFrame: 2 hours
measure: Credibility and Effectiveness of the placebo analgesia expectation; adapted Version of the Context Model Questionnaire; Kontextmodellfragebogen (KMF)
timeFrame: 2 hours
measure: multidimensional sensitivities questionnaire (Mehrdimensionaler Befindlichkeitsfragebogen (MDBF))
timeFrame: 2 hours
measure: sociodemographic questionnaire (Soziodemographischer Fragebogen (SDD))
timeFrame: 2 hours
measure: Revised Life Orientation Test (LOT-R)
timeFrame: 2 hours
measure: NEO five-factor inventory (NEO-FFI)
timeFrame: 2 hours
measure: questionnaire on competence and locus of control (Fragebogen zu Kompetenz- und Kontrollüberzeugungen (FKK))
timeFrame: 2 hours
measure: Anxiety and Depression Scale (HADS-D)
timeFrame: 2 hours
measure: Beliefs in holistic health and holistic treatments; Complementary and Alternative Medicine Beliefs Intentory (CAMBI)
timeFrame: 2 hours
measure: Desire for Relief Scale (DRS)
timeFrame: 2 hours
measure: subjective intensity and unpleasantness ratings of heat pain threshold
timeFrame: 2 hours
measure: objective heat pain threshold
timeFrame: 2 hours
Other outcomes:
Locations:
city: Basel
country: Switzerland
facility: University of Basel
Study officials:
affiliation: Clinical Psychology and Psychotherapy, Department of Psychology, University of Basel
name: Jens Gaab, Prof
role: STUDY_CHAIR
References:
citation: Locher C, Buergler S, Frey Nascimento A, Kost L, Blease C, Gaab J. Lay perspectives of the open-label placebo rationale: a qualitative study of participants in an experimental trial. BMJ Open. 2021 Aug 18;11(8):e053346. doi: 10.1136/bmjopen-2021-053346.