Healthy
Conditions
Keywords
Gastrointestinal Symptoms, Placebo Effect, Open-Label Placebo
Brief summary
The present study is aimed at exploring whether positive expectations of receiving a three-week treatment with a probiotic supplement (in fact a placebo) improve symptoms of gastrointestinal distress and promote physical and emotional well-being in healthy individuals with mild gastrointestinal symptoms. At first, a comparison is planned between (1) a classic deceptive placebo manipulation (Deceptive Placebo group, DP), and (2) a control condition (Control group, C), in which no placebo substance will be administered. After the three-week waiting list, the Control group will be invited to take the placebo probiotic pills in an open-label fashion (Open Label Placebo, OLP). Specifically, participants will be informed that the pills are inert placebos. An exploratory analysis will help to clarify whether the OLP paradigm leads to significant effects, based on a within-group (C- OLP) and between-group comparison (DP-OLP).
Interventions
OTHERPlacebo probiotic
Three-week consumption of placebo probiotic capsules passed off as being actual probiotics
OTHEROpen-Label Placebo probiotic
Participants of the Control group will be switched to this condition after three weeks and receive placebo probiotic capsules for the following three-weeks of no intervention. Specifically, they will be honestly informed that the capsules are inert placebos.
OTHERControl-no treatment
For the first three weeks, the Control group will not be exposed to any intervention.
Sponsors
Catholic University of the Sacred Heart
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
20 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Age between 20 and 65 * Individuals with mild gastrointestinal symptoms (e.g., digestive issues, acid reflux, constipation) such that normal every-day activities are not severly compromised.
Exclusion criteria
* Individuals with a diagnosis of functional gastrointestinal disorders (e.g., irritable bowel syndrome, ulcerative colitis, chronic inflammatory bowel diseases). * Individuals suffering from neurodegenerative diseases and/or psychiatric conditions * Individuals taking probiotic supplementation at the time of enrollment in the study
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Change from Baseline in the Gastrointestinal Symptom Rating Scale (GSRS) total score at 3 weeks. | Baseline and 3 weeks |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline in Stool Form as assessed by means of the Bristol Stool Scale | Day 2/3 and day 19/20 from Baseline | The Bristol stool scale is a diagnostic medical tool designed to classify the form of human stool into seven categories. |
| Change from Baseline in Fatigue Levels as assessed by means of the Multidimensional Fatigue Inventory (MFI-20) at 3 weeks. | Baseline and 3 weeks | Items are scored 1-5, with 10 \[fatigue-\]positively phrased items reverse scored (items 2, 5, 9, 10, 13, 14, 16, 17, 18, 19). In the final score, high scores represent more fatigue. |
| Change from Baseline in the Digestion-Associated Quality Of Life Questionnaire (DQLQ) total score at 3 weeks. | Baseline and 3 weeks | — |
| Change from Baseline in Positive and Negative affect as assessed by means of the Positive and Negative Affect Schedule (PANAS) at 3 weeks. | Baseline and 3 weeks | — |
| Change from Baseline in Stress Levels as assessed by means of the Perceived Stress Scale (PSS) 3 weeks. | Baseline and 3 weeks | The scale comprises of 10 items, with scores ranging from 0 ( = Never) to 4 ( = Very Often). Scores ranging from 0-13 would be considered low stress. Scores ranging from 14-26 would be considered moderate stress. Scores ranging from 27-40 would be considered high perceived stress. |
| Change from Baseline in Sleepiness Levels as assessed by means of the The Epworth sleepiness scale at 3 weeks. | Baseline and 3 weeks | Final total score ranges from 0 to 24. Scores from 0 to 10 show average (normal) daytime sleepiness. A result from 11 to 24 indicates excessive (abnormal) daytime sleepiness. |
Countries
Italy
Contacts
Primary ContactDiletta Barbiani
Outcome results
None listed