Does the Subject's Understanding of Underlying Placebo Mechanisms Compensate for the Loss of Efficacy Associated With the Disclosure of the Use of a Placebo
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 126
- 试验地点
- 2
- 主要终点
- Pain intensity: Visual Analogue Scale (VAS)
研究概览
简要总结
The investigators are investigating whether, when given detailed information about underlying placebo mechanisms and pain, subjects will have a response similar to that of those subjected to a procedure in which they receive a conventional placebo treatment (associated with deception).
STUDY DESIGN: This is a non-inferior parallel, controlled and randomized, single blind trial.
POPULATION: The investigators will include in the study 126 subjects without known pathology. Participants will then be divided into 2 groups on a randomized basis.
METHODOLOGY: Each subject will undergo three sessions of Cold Pressure Test (CPT), a cold pain stimulation method: calibration, condition of interest (conventional placebo or educated placebo) and control. The investigators' main judgment criterion is be the difference in pain intensity experienced on the visual analog scale between the CPT control and the CPT under the condition of interest.
This study will allow the investigators to rule on the non-inferiority of an educated open label placebo compared to a conventional placebo in the context of an acute painful stimulation.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Participant)
盲法说明
Only the subjects in the the conventional placebo group will be masked. In the educated open label placebo group, subjects will be aware that the cream is inert.
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Person affiliated to Social Security
- •Informed consent, written and signed by the subject.
排除标准
- •Persons referred to in Articles L1121-5 to L1121-8 of the Public Health Code (CSP), which corresponds to all protected persons: pregnant women, parturient women, nursing mothers, persons deprived of their liberty by judicial or administrative decision, persons subject to a legal protection measure, cannot be included in clinical trials.
- •Persons with a pathology against indicating the use of CPT experimentally induced pain :
- •Any pathologies affecting the venous, arterial or lymphatic system
- •Cardiac disorders
- •Frostbite
- •Arthritis
- •Lupus erythematosus
- •Allergy to Cremafluid® cream
- •Person with concomitant treatment that modifies sensitivity to pain, chronic or acute at the time of the experiment, such as analgesics, psychotropic drugs or anti-inflammatories.
研究组 & 干预措施
Educated open label placebo
These subjects will undergo all the same procedures as in the control group. But before the placebo CTP, they will watch a short movie explaining placebo mechanisms. While applying the placebo cream, they will be told that the cream is inert (placebo), efficient to decrease pain caused by cold and the mechanisms seen in the movie will take place.
干预措施: Educational movie on placebo mechanisms (Other)
Conventional placebo
These subjects will watch a video on hand washing. While applying the placebo cream, they will be told that this cream is effective to decreased pain caused by cold.
干预措施: Informative movie on hand washing (Other)
结局指标
主要结局
Pain intensity: Visual Analogue Scale (VAS)
时间窗: At the end of the CPT procedure, within 30 seconds after the removal of the hand from the CPT cold water tank.
Evaluated with a Visual Analogue Scale (VAS) from 0 to 100 mm, with a non inferiority margin at 10 mm and a standard deviation at 22 mm.
次要结局
- Anxiety respiratory frequency change(During the CPT procedure)
- Anxiety blood pressure change(During the CPT procedure)
- Knowledge of placebo's mechanisms(At the beginning and end of the CPT procedures)
- Perception of the investigator(At the end of the study, when all CPT procedures have been carried out, within 10 minutes after the last immersion)
- The Perceived Awareness of the Research Hypothesis Scale questionnaire(At the end of the study, when all CPT procedures have been carried out, within 10 minutes after the last immersion)