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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT06940596




Registration number
NCT06940596
Ethics application status
Date submitted
31/03/2025
Date registered
23/04/2025
Date last updated
10/07/2025

Titles & IDs
Public title
Exclude or Expose in Irritable Bowel Syndrome: What Works for Whom and How?
Scientific title
Exclude or Expose in Irritable Bowel Syndrome: What Works for Whom, and How? A Randomized Controlled Trial of Internet-Delivered FODMAP Diet Versus Exposure-Based Cognitive Behavioral Therapy
Secondary ID [1] 0 0
2024
Secondary ID [2] 0 0
CT31293
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Irritable Bowel Syndrome (IBS) 0 0
Intestinal Diseases 0 0
Gastrointestinal Disease 0 0
Condition category
Condition code
Oral and Gastrointestinal 0 0 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon
Other 0 0 0 0
Research that is not of generic health relevance and not applicable to specific health categories listed above

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - FODMAP Diet
BEHAVIORAL - Exposure-based Cognitive Behavioral Therapy

Experimental: FODMAP Diet - Fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) Diet is a 12-week online intervention with dietitian support.

Experimental: Exposure-based Cognitive Behavioral Therapy (E-CBT) - Exposure-based Cognitive Behavioral Therapy is a 12-week online intervention with psychologist support.


Other interventions: FODMAP Diet
The intervention is an online diet program. The diet is the low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet. It is a 3-phase diet which involves: 1.Phase 1 FODMAP restriction: restrict foods high or moderate in FODMAPs and swap these for low FODMAP alternatives; 2. Phase 2 FODMAP reintroduction: continue to follow a low FODMAP diet and complete a series of food challenges to understand which foods and FODMAPs are tolerated and which trigger symptoms; 3. Phase 3 FODMAP personalization: include well-tolerated foods and FODMAPs back into the diet, and restrict poorly tolerated foods and FODMAPs to a level needed to maintain symptom relief. The online FODMAP program is a self-directed diet program with support from an online clinician (Accredited Practicing Dietitian \[APD\]). The content is delivered over 12 weeks. After each module participants will complete homework activities and questions and submit them to the dietitian for feedback.

BEHAVIORAL: Exposure-based Cognitive Behavioral Therapy
The intervention is an online behavioral therapy program. The behavioral therapy is Exposure-based Cognitive Behavioral Therapy (E-CBT) Program. The E-CBT program is organised into six steps to be completed over 12 weekly modules with support from an online clinician (Psychologist). The first step contains a rationale for the treatment and instructions on self-observation. Steps 2, 3 and 4 contain a presentation of a psychological model of IBS and continued self-observation exercises. The fifth step covers exposure exercises, divided into three categories; (1) exercises that provoke symptoms, (2) abolishment of behaviors that serve to control symptoms, (3) exposure to situations where symptoms were unwanted. The final step (Step 6) includes how to handle relapses into avoidance behaviors and how to maintain a widened behavioral repertoire. After each module participants will be directed to complete homework activities and questions and submit them to the psychologist for feedback.

Intervention code [1] 0 0
Other interventions
Intervention code [2] 0 0
BEHAVIORAL
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Gastrointestinal Symptom Rating Scale-Irritable Bowel Syndrome (GSRS-IBS )
Timepoint [1] 0 0
Measured weekly between baseline (prior to intervention) and after intervention completed (week 12).
Secondary outcome [1] 0 0
Change from baseline in Gastrointestinal Symptom Rating Scale-Irritable Bowel Syndrome (GSRS-IBS)
Timepoint [1] 0 0
Baseline and 3-and 6 month follow up time points after intervention completed (week 12).
Secondary outcome [2] 0 0
Change from baseline in Irritable Bowel Syndrome - Symptom Severity Score (IBS-SSS) questionnaire
Timepoint [2] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [3] 0 0
Change from baseline in IBS quality of life (IBS-QOL) questionnaire
Timepoint [3] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [4] 0 0
Change from baseline in Nine Item ARFID (Avoidant Restrictive Food Intake Disorder) Screen (NIAS) questionnaire
Timepoint [4] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [5] 0 0
Change from baseline in Fear of Food Questionnaire (FFQ) questionnaire
Timepoint [5] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [6] 0 0
Change from baseline in Patient Health Questionnaire-12 (PHQ-12) (derived from PHQ-15) questionnaire
Timepoint [6] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [7] 0 0
Change from baseline in Generalized anxiety disorder (GAD-7) questionnaire
Timepoint [7] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [8] 0 0
Change from baseline in Patient Health Questionnaire (PHQ-9) questionnaire
Timepoint [8] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [9] 0 0
Change from baseline in Gastrointestinal Specific Anxiety (GSA) measured using Visceral Sensitivity Index (VSI)
Timepoint [9] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [10] 0 0
Change from baseline in Avoidance behavior measured using Irritable Bowel Syndrome-Behavioural Responses Questionnaire (IBS-BRQ)
Timepoint [10] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [11] 0 0
Change from baseline in Total FODMAP intake measured using 3-day food diary
Timepoint [11] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [12] 0 0
Change from baseline in stool frequency and consistency using 7-day stool diary based on Bristol Stool Form Scale (BSFS)
Timepoint [12] 0 0
Baseline, after intervention completed (week 12), and at follow up time points of 3-and 6 months following the 12-week intervention.
Secondary outcome [13] 0 0
Gastrointestinal microbiome composition and function using stool sample using OMNIgene GUT
Timepoint [13] 0 0
Gastrointestinal microbiome composition and function will be measured 2nd weekly between baseline (prior to intervention) and after intervention completed (week 12) as exploratory mediators.
Secondary outcome [14] 0 0
Individual FODMAPs' intake using 3-day food diary
Timepoint [14] 0 0
Will be measured 2nd weekly between baseline (prior to intervention) and after intervention completed (week 12) as exploratory mediators.
Secondary outcome [15] 0 0
Gastrointestinal Symptom Rating Scale-Irritable Bowel Syndrome GSRS-IBS
Timepoint [15] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [16] 0 0
IBS quality of life (IBS-QOL) questionnaire
Timepoint [16] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [17] 0 0
Fear of Food Questionnaire (FFQ) questionnaire
Timepoint [17] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [18] 0 0
Nine Item ARFID (Avoidant Restrictive Food Intake Disorder) Screen (NIAS) questionnaire
Timepoint [18] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [19] 0 0
Patient Health Questionnaire-12 (PHQ-12) (derived from PHQ-15) questionnaire
Timepoint [19] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [20] 0 0
Patient Health Questionnaire (PHQ-9) questionnaire
Timepoint [20] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [21] 0 0
Generalized anxiety disorder (GAD-7) questionnaire
Timepoint [21] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [22] 0 0
Gastrointestinal microbiome composition and function using stool sample using a stool sample collection kit.
Timepoint [22] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [23] 0 0
IBS subtype using 7-day stool diary based on Bristol Stool Form Scale (BSFS).
Timepoint [23] 0 0
Baseline (prior to start of intervention) as an exploratory moderator.
Secondary outcome [24] 0 0
Client Satisfaction Questionnaire
Timepoint [24] 0 0
End of the 12-week intervention and at 3-and 6 months follow up time points after 12-week intervention..
Secondary outcome [25] 0 0
Proportion of participants who achieve a change from baseline in Gastrointestinal Symptom Rating Scale-Irritable Bowel Syndrome (GSRS-IBS) of >30% total score
Timepoint [25] 0 0
Baseline and after intervention completed (week 12)
Secondary outcome [26] 0 0
Proportion of participants who achieve a change from baseline in Irritable Bowel Syndrome - Symptom Severity Score (IBS-SSS) of =50 points total score.
Timepoint [26] 0 0
Baseline and after intervention completed (week 12)

Eligibility
Key inclusion criteria
Each participant must meet all of the following criteria to be enrolled in this trial:

* Living in Australia or the United States
* Aged 18 years or older
* Body Mass Index (BMI) [Equation]18.5kg/m2 and [Equation] 34.9kg/m2
* Diagnosed with IBS by a General Practitioner, Family Physician, or Gastroenterologist, or Advanced Specialist Dietitian
* Currently fulfill Rome IV criteria for IBS
* Symptomatic at the time of recruitment (IBS-SSS > 175)
* Access to a computer and internet
* Sufficient English language and computer skills to complete a text-based online treatment
* Willing to make dietary or behavioral changes in line with the allocated treatment program
* Ability to provide informed consent
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Patients meeting any of the following criteria will be excluded from the trial:

* Presence or known history of other GI disease (e.g. coeliac disease, Inflammatory Bowel Disease) or history of gastrointestinal cancer
* History of major gastrointestinal surgery (not appendectomy, cholecystectomy or hemorrhoidectomy)
* Individuals who report alarm symptoms (e.g., blood in stool, recent unexplained/unintentional weight loss >5% body weight, a recent change in bowel habits if >50 years, family history of gastrointestinal cancer or gastrointestinal diseases, large volumes of diarrhea occurring at night, fever associated with gut symptoms, recurrent vomiting, persistent unexplained iron deficiency) will be excluded if appropriate medical investigations have not been conducted, unless written medical approval is provided from a general practitioner, family physical, or gastroenterologist.
* Diagnosis of major disease that could explain current gastrointestinal symptoms such as severe diabetic, cardiac, liver, neurological, neuropathy disease
* History or current diagnosis of psychotic disorder or bipolar disorder
* Current diagnosis of substance abuse disorder or major depressive disorder or active suicidal ideation
* History or current diagnosis of an eating disorder
* Current enteral/parenteral feeding or use of supplemental feeds (e.g. Ensure)
* Pregnant or lactating or planning to become pregnant during the 12-week intervention period
* Commenced or change in dose of antibiotics and medications that potentially affect the gastrointestinal transit (e.g. anti-diarrheals and laxatives) in the 3 months preceding study commencement.
* Commenced taking or changed dose of probiotics, prebiotics, fibre supplements and digestive enzymes in the 3 months preceding study commencement
* Commenced or change dose in psychotropic medication in the 3 months preceding study commencement
* Are currently undertaking behavioral therapy for IBS (including cognitive behavioral therapy, CBT), or have undertaken clinician-delivered behavioral therapy for the treatment of IBS
* Are currently undertaking or have undertaken a dietitian-prescribed and delivered restrictive diet for IBS (e.g., FODMAP diet).

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not applicable
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment hospital [1] 0 0
University of Melbourne - Melbourne
Recruitment postcode(s) [1] 0 0
3010 - Melbourne

Funding & Sponsors
Primary sponsor type
Other
Name
University of Melbourne
Address
Country
Other collaborator category [1] 0 0
Other
Name [1] 0 0
Monash University
Address [1] 0 0
Country [1] 0 0

Ethics approval
Ethics application status

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Associate Professor Jessica Biesiekierski
Address 0 0
University of Melbourne
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Jessica Biesiekierski, A/Prof
Address 0 0
Country 0 0
Phone 0 0
+61 499 272 673
Fax 0 0
Email 0 0
Contact person for scientific queries

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Potential data shared includes:

* Individual participant data that underlie the results reported in the article after de-identification (text, tables, figures and appendices)
* Trial protocol
* Statistical Analysis Plan
* Participant Information Consent Form

Supporting document/s available: Study protocol, Statistical analysis plan (SAP), Informed consent form (ICF), Clinical study report (CSR), Analytic code
When will data be available (start and end dates)?
The IPD and supporting information will be available beginning 3 months following analysis and article publication for 15 years.
Available to whom?
The IPD and supporting information will be made available for use by future researchers from a recognized research institution whose proposed use of the data has been ethically reviewed and approved by an independent committee and who accept University of Melbourne conditions for access.
Available for what types of analyses?
How or where can data be obtained?
IPD available at link: https://figshare.unimelb.edu.au/


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

No documents have been uploaded by study researchers.