Eating Disorder Chatbot Optimization
July 20, 2026 updated by: Ellen E. Fitzsimmons-Craft, Washington University School of Medicine
Optimizing an Automated Chatbot to Achieve Efficient, Scalable Treatment for Eating Disorders
The purpose of this study is to optimize an automated digital chatbot intervention for adults with clinical or subclinical eating disorders.
Study Overview
Status
Recruiting
Conditions
Intervention / Treatment
Detailed Description
Eating disorders (EDs) are common-affecting an estimated 10% of individuals in their lifetimes-and have disabling consequences being associated with high psychiatric comorbidity, impairment, and mortality.
Despite this, less than 20% of individuals with an ED ever receive treatment.
When individuals do seek treatment, many are not evidence-based and come with high costs and burden on the healthcare system.
One solution to this is a chatbot intervention that is evidence-based, affordable, and accessible for people with EDs.
This project will assess four candidate components of a cognitive behavioral therapy (CBT)-based chatbot to determine the optimal chatbot package.
CBT is the recommended first-line treatment for EDs, yet there is no research to date on which components are most effective or needed for meaningful change in ED psychopathology.
In this study the intervention will be divided into four components targeting: (1) over-evaluation of weight and shape; (2) dietary restraint; (3) emotion dysregulation; and (4) resisting urges to binge.
The investigators will recruit 800 adults with a binge/purge-type ED who are not currently in treatment and randomly assign participants to one of 16 experimental conditions (each combination from 1 to all 4 components) or the waitlist-control group.
Participants will be assessed on changes in ED psychopathology, ED behavior frequencies, comorbid symptoms (i.e., depression, anxiety), and clinical impairment at 1-, 2-, and 6-months following randomization.
An optimized package of these candidate components that is most effective, while remaining efficient, will be identified using multiphase optimization strategy (MOST).
The investigators' established relationships with industry and non-profit partners will ensure this optimized package has high potential for scalability and dissemination into the community.
Study Type
Interventional
Enrollment (Estimated)
800
Phase
- Phase 2
Contacts and Locations
This section provides the contact details for those conducting the study, and information on where this study is being conducted.
Study Contact
- Name: Marianna B. Horton, B.S./B.A.
- Phone Number: 3149355843
- Email: m.horton@wustl.edu
Study Contact Backup
- Name: Nathalie A. Gullo, B.S./B.A.
- Phone Number: 6469195177
- Email: gullo@wustl.edu
Study Locations
-
-
Missouri
-
St Louis, Missouri, United States, 63105
- Recruiting
- Washington University in St. Louis
-
Contact:
- Marianna B. Horton, B.S./B.A.
- Phone Number: 3149355843
- Email: m.horton@wustl.edu
-
Principal Investigator:
- Ellen Fitzsimmons-Craft, Ph.D.
-
-
Participation Criteria
Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.
Eligibility Criteria
Ages Eligible for Study
- Adult
- Older Adult
Accepts Healthy Volunteers
No
Description
Inclusion Criteria:
- 18+ years old
- Owns a smartphone
- Speaks English
- US resident
- Screens for a clinical or subclinical eating disorder
- Low suicidality
- Not currently in treatment for an eating disorder
- Does not have a medical condition or take medications that impact appetite/weight
- Not currently pregnant
Exclusion Criteria:
- Below 18 years of age
- Does not own a smartphone
- Does not speak English
- Lives outside the US
- Screens as: at risk for an eating disorder, anorexia nervosa, atypical anorexia nervosa, avoidant/restrictive food intake disorder, or not at risk for an ED
- High suicidality
- In treatment for an eating disorder
- Has a medical condition or takes medication(s) that impact appetite/weight
- Currently pregnant
Study Plan
This section provides details of the study plan, including how the study is designed and what the study is measuring.
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: Randomized
- Interventional Model: Factorial Assignment
- Masking: None (Open Label)
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Chatbot targeting weight & shape over-evaluation (WSC)
Participant will have access to the chatbot component addressing weight & shape over-evaluation.
Participant will receive scheduled targeted practice for the weight & shape over-evaluation component.
At any time, participant will have access to initiate practice in assigned study component.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting dietary restraint (DR)
Participant will have access to the chatbot component addressing dietary restraint.
Participant will receive scheduled targeted practice for the dietary restraint component.
At any time, participant will have access to initiate practice in assigned study component.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting emotion dysregulation (ED)
Participant will have access to the chatbot component addressing emotion dysregulation.
Participant will receive scheduled targeted practice for the emotion dysregulation component.
At any time, participant will have access to initiate practice in assigned study component.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting resisting urges to binge (UB)
Participant will have access to the chatbot component addressing resisting urges to binge.
Participant will receive scheduled targeted practice for the resisting urges to binge component.
At any time, participant will have access to initiate practice in assigned study component.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting WSC and DR
Participant will have access to the chatbot components addressing weight & shape over-evaluation and dietary restraint.
Participant will receive scheduled targeted practice for the weight & shape over-evaluation and dietary restraint components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting WSC and ED
Participant will have access to the chatbot components addressing weight & shape over-evaluation and emotion deregulation.
Participant will receive scheduled targeted practice for the weight & shape over-evaluation and emotion dysregulation components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting WSC and UB
Participant will have access to the chatbot components addressing weight & shape over-evaluation and resisting urges to binge.
Participant will receive scheduled targeted practice for the weight & shape over-evaluation and resisting urges to binge components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting DR and ED
Participant will have access to the chatbot components addressing dietary restraint and emotion deregulation.
Participant will receive scheduled targeted practice for the dietary restraint and emotion dysregulation components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting DR and UB
Participant will have access to the chatbot components addressing dietary restraint and resisting urges to binge.
Participant will receive scheduled targeted practice for the dietary restraint and resisting urges to binge components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting ED and UB
Participant will have access to the chatbot components addressing emotion dysregulation and resisting urges to binge.
Participant will receive scheduled targeted practice for the emotion dysregulation and resisting urges to binge components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting ED; UB; and DR
Participant will have access to the chatbot components addressing emotion dysregulation, resisting urges to binge, and dietary restraint.
Participant will receive scheduled targeted practice for the emotion dysregulation, resisting urges to binge, and dietary restraint components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting ED; UB; and WSC
Participant will have access to the chatbot components addressing emotion dysregulation, resisting urges to binge, and weight and shape over-evaluation.
Participant will receive scheduled targeted practice for the emotion dysregulation, resisting urges to binge, and weight and shape over-evaluation components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting ED; DR; and WSC
Participant will have access to the chatbot components addressing emotion dysregulation, dietary restraint, and weight and shape over-evaluation.
Participant will receive scheduled targeted practice for the emotion dysregulation, dietary restraint, and weight and shape over-evaluation components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting UB; DR; and WSC
Participant will have access to the chatbot components addressing resisting urges to binge, dietary restraint, and weight and shape over-evaluation.
Participant will receive scheduled targeted practice for the resisting urges to binge, emotion dysregulation, dietary restraint and weight, and shape over-evaluation components.
At any time, participant will have access to initiate practice in assigned study components
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
Experimental: Chatbot targeting UB; DR; ED; and WSC
Participant will have access to the chatbot components addressing resisting urges to binge, dietary restraint, emotion dysregulation, and weight and shape over-evaluation.
Participant will receive scheduled targeted practice for the resisting urges to binge, emotion dysregulation, dietary restraint, emotion dysregulation, and weight and shape over-evaluation components.
At any time, participant will have access to initiate practice in assigned study components.
|
Wysa is a digital rules-based chatbot program platform offering cognitive-behavioral therapy-based guided self-help modules.
Participants in an arm with access to Wysa will engage with the digital chatbot program daily for eight weeks.
|
|
No Intervention: Referral to seek services
Those randomized to receive all chatbot components "off" will receive a referral to seek services.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
ED psychopathology; ED Examination-Questionnaire (EDE-Q)
Time Frame: 6 months
|
The EDE-Q is a 28-item inventory derived from an ED diagnostic interview, which asks self-reported concerns with weight and shape, and engagement in ED behaviors, over the last 28 days.
Each item is scored from 0-6, with 0 being "No days" and 6 being "Every day".
An average is taken of all items participants respond to for a total global score (with possible scores ranging from 0 to 6), where higher scores indicate greater symptomology.
|
6 months
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
ED behaviors from the EDE-Q; Muscle Building Subscale from the Eating Pathology Symptoms Inventory (EPSI)
Time Frame: 6 months
|
The EDE-Q will also be used to gauge self-reported engagement in ED behaviors.
Additionally, the EPSI Muscle Building subscale will be used which is a 5-item questionnaire that asks self-reported frequency of muscle building behaviors and attitudes over the last 28 days.
Each item is scored from 0 ("Never") to 4 ("Very Often").
Subscale score is calculated by summing items participants respond to (scores may range from 0 to 20), and higher scores indicate greater symptomology.
|
6 months
|
|
Depression; Patient Health Questionnaire (PHQ-9)
Time Frame: 6 months
|
The PHQ-9 is a 9-item scale asking about self-reported depressive symptoms and suicidality over the past two weeks.
All items are scored from 0 ("Not at all") to 3 ("Nearly every day").
Items participants respond to are summed (possible scores ranging from 0 to 27), and higher scores indicate greater symptomology.
|
6 months
|
|
Anxiety; Generalized Anxiety Disorder (GAD-7)
Time Frame: 6 months
|
The GAD-7 is a 7-item scale assessing self-reported symptoms of anxiety over the past two weeks.
All items are scored from 0 ("Not at all") to 3 ("Nearly every day").
Items participants respond to are summed (possible scores ranging from 0 to 21), and higher scores indicate greater symptomology.
|
6 months
|
|
Clinical Impairment; Clinical Impairment Assessment (CIA)
Time Frame: 6 months
|
The CIA is a 16-item measure that assesses self-reported impairment, or impact on one's life, resulting from eating, weight, or shape in the last 28 days.
All items are scores from 0 ("Not at all") to 3 ("A lot").
Items participants respond to are summed (possible scores ranging from 0 to 48), and higher scores indicate greater impairment.
|
6 months
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Investigators
- Principal Investigator: Ellen Fitzsimmons-Craft, Ph.D., Washington University School of Medicine
Study record dates
These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.
Study Major Dates
Study Start (Actual)
July 17, 2026
Primary Completion (Estimated)
July 31, 2029
Study Completion (Estimated)
July 31, 2029
Study Registration Dates
First Submitted
October 15, 2025
First Submitted That Met QC Criteria
October 15, 2025
First Posted (Actual)
October 20, 2025
Study Record Updates
Last Update Posted (Actual)
July 21, 2026
Last Update Submitted That Met QC Criteria
July 20, 2026
Last Verified
July 1, 2026
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- 202505037
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
YES
IPD Plan Description
Study protocol and informed consent form
IPD Sharing Supporting Information Type
- STUDY_PROTOCOL
- ICF
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
No
Studies a U.S. FDA-regulated device product
No
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.