May 1, 2019
May 16, 2019
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.
|Active Comparator: 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.
Other: Educational movie on placebo mechanisms
Educational movie on placebo mechanisms : animated video, duration : 12 minutes. It will be followed by the CPTs : experimentally induced pain by keeping the non dominant hand in cold water (1° Celsius) for a limited time. The duration of immersion is personal and calibrated to be around to ensure that the intensity of pain will be homogeneous (around 7/10 on the visual analogue scale with no treatment)
|Placebo Comparator: 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.
Other: Informative movie on hand washing
Animated video, duration : 11 minutes. It will be followed by the CPTs : experimentally induced pain by keeping the non dominant hand in cold water (1° Celsius) for a limited time. The duration of immersion is personal and calibrated to be around to ensure that the intensity of pain will be homogeneous (around 7/10 on the visual analogue scale with no treatment).
- Person affiliated to Social Security
- Informed consent, written and signed by the subject.
- 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
- 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
Contact: Nicolas PINSAULT 04 76 76 52 56 email@example.com
Contact: Carole ROLLAND 04 76 76 69 03 firstname.lastname@example.org
Saraeve Graham Longsworth
Principal Investigator: Leo DRUART TIMC IMAG Thémas team
Principal Investigator: SaraEve GRAHAM LONGSWORTH TIMC IMAG Thémas team
Study Director: Nicolas PINSAULT TIMC IMAG Thémas team
Kaptchuk TJ, Friedlander E, Kelley JM, Sanchez MN, Kokkotou E, Singer JP, Kowalczykowski M, Miller FG, Kirsch I, Lembo AJ. Placebos without deception: a randomized controlled trial in irritable bowel syndrome. PLoS One. 2010 Dec 22;5(12):e15591. doi: 10.1371/journal.pone.0015591.
Locher C, Frey Nascimento A, Kirsch I, Kossowsky J, Meyer A, Gaab J. Is the rationale more important than deception? A randomized controlled trial of open-label placebo analgesia. Pain. 2017 Dec;158(12):2320-2328. doi: 10.1097/j.pain.0000000000001012.
Streff A, Kuehl LK, Michaux G, Anton F. Differential physiological effects during tonic painful hand immersion tests using hot and ice water. Eur J Pain. 2010 Mar;14(3):266-72. doi: 10.1016/j.ejpain.2009.05.011. Epub 2009 Jun 21.
Carvalho C, Caetano JM, Cunha L, Rebouta P, Kaptchuk TJ, Kirsch I. Open-label placebo treatment in chronic low back pain: a randomized controlled trial. Pain. 2016 Dec;157(12):2766-2772. Erratum in: Pain. 2017 Feb;158(2):365.