Evaluation of a Web-Based Intervention for Bulimia Nervosa

Study Overview
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Brief Summary
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This study evaluates the effectiveness of a web-based intervention specifically designed for patients with Bulimia Nervosa (BN) in a blinded randomized controlled trial. After a sign-up process, a diagnostic interview, and a baseline assessment, eligible participants will be randomly allocated either to (1) an intervention group including the online web-based intervention for BN or (2) a waitlist control group with delayed access to the intervention (12 weeks). The program comprises six mandatory weekly sessions and six modular specialization areas resulting in a treatment period of 12 weeks. Minimal guidance is provided via a chat function. Assessments will be conducted at pretreatment (study entrance), six weeks after baseline (mid-treatment), and 12 weeks after baseline (post-treatment). The investigators expect that the intervention group will show lower frequencies of binge eating episodes and compensatory behavior as the primary outcome variables after the 12 weeks of treatment compared to a waitlist control condition. Moreoever, the investigators assume that there will be a higher reduction in global eating disorder symptoms, comorbid psychopathology, and a higher increase in well-being and self-esteem over 12 weeks in the intervention group compared to the waitlist control group. Finally, the investigators expect that the intervention group will demonstrate a significantly higher reduction in functional impairment, substantially better restoration of work capacity, and an improved ability to regulate emotions after the 12 weeks of treatment.

Detailed Description
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Background: Bulimia Nervosa (BN) is characterized by persistent episodes of uncontrolled eating and inappropriate compensatory behaviors, associated with marked impairments in physical and mental health, social integration, professional performance, and overall quality of life. Although cognitive-behavioral therapies are effective for bulimia nervosa, access to specialized treatment in Germany is limited due to patient-related barriers and insufficient healthcare resources. Internet-based interventions can overcome this treatment gap and reduce the burden of BN for both patients and the healthcare system by making evidence-based interventions more accessible. Goal: This study evaluates the effectiveness of a web-based intervention specifically designed for patients with BN in a blinded randomized controlled trial. Method: After a sign-up process, a structured diagnostic interview, and a baseline assessment, eligible participants will be randomly allocated either to (1) an intervention group including the online web-based intervention for BN or (2) a waitlist control group with delayed access to the intervention (12 weeks). The program comprises six mandatory weekly sessions covering topics related to eating behaviors, emotion regulation, and stress management, followed by an optional set of up to six modular specialization areas based on individual therapy goals. Moreover, minimal guidance is included, consisting of technical support and answering questions via a chat function. Assessments will be conducted at pretreatment (study entrance), six weeks after baseline (mid-treatment), and 12 weeks after baseline (post-treatment). The primary outcome will be the number of binge eating episodes and compensatory behaviors. Secondary measures include global eating pathology, comorbid psychopathology, quality of life, self-esteem, emotion regulation, work capacity, and functional impairments. Statistical Analyses: An intention-to-treat analysis will be performed to examine differences between the intervention and the control group in the change of eating disorder symptoms and secondary outcomes from pre- to post-treatment. Hypotheses: The investigators expect that the intervention group will show lower frequencies of binge eating episodes and compensatory behavior as the primary outcome variables after the 12 weeks of treatment compared to a waitlist control condition. The investigators assume that there will be a higher reduction in global eating disorder symptoms, comorbid psychopathology, and a higher increase in well-being and self-esteem over 12 weeks in the intervention group compared to the waitlist control group. Moreover, the investigators expect that the intervention group will demonstrate a significantly higher reduction in functional impairment, substantially better restoration of work capacity, and an improved ability to regulate negative emotions after the 12 weeks of treatment.

Official Title
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Evaluation of a 12-Week Web-Based Intervention for Bulimia Nervosa: A Randomized Controlled Trial

Conditions
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Bulimia Nervosa

Intervention / Treatment
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* Other: Selfapy for Bulimia Nervosa


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: sufficient German language skills (C1) permanent internet access during the study period meeting the diagnostic criteria for Bulimia Nervosa according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) Exclusion criteria: current severe depressive episode acute suicidality comorbid bipolar disorder or psychotic disorders acute substance dependence current psychotherapy or pharmacotherapy for eating disorders Body Mass Index (BMI) below 18.5

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized controlled trial with an intervention group and a waiting list control group
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Intervention Group<br>Web-based intervention (Selfapy for Bulimia Nervosa) | Other: Selfapy for Bulimia Nervosa<br>* Web-based intervention for Bulimia Nervosa with six mandatory weekly sessions covering topics related to eating behaviors, emotion regulation, and stress management, followed by an optional set of up to six modular specialization areas based on individual therapy goals. During the intervention, participants can access an online chat providing crisis management, answering questions concerning the exercises, and technical support. The chat does not include the opportunity to discuss individual topics and concerns about treatment.<br>|
| No Intervention: Waitlist Control Group<br>12-week waiting period | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in the frequency of binge eating episodes and compensatory behavior within the last 28 days | The Eating Disorders Examination Questionnaire (EDE-Q; Berg et al., 2012) captures the frequency of binge eating episodes and compensatory behavior within the last 28 days using 6 items. Higher values indicate a higher frequency of relevant eating disorder episodes. | 0 weeks, 6 weeks, 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in global eating psychopathology | The Eating Disorders Examination Questionnaire (EDE-Q; Berg et al., 2012) allows assessing global eating psychopathology based on 22 items. Mean scores range from 0 to 6, with higher values indicating a higher global eating psychopathology. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in the weekly frequency of binge eating episodes, compensatory behavior, and regular eating | The Weekly Binges Questionnaire (WBQ; Munsch et al., 2007) assesses the frequency of binge eating episodes, compensatory behavior, and regular eating by asking participants to count the number of binge eating episodes, the number of compensatory behaviors, and the number of days with regular eating habits. While a higher number of binges and compensatory behaviors indicates a higher symptomatology, a higher number of regular eating days indicates a lower symptomatology. | 0 weeks, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 7 weeks, 8 weeks, 9 weeks, 10 weeks, 11 weeks, 12 weeks | 
| Changes in everyday eating disorder symptoms | Ecological momentary assessment (EMA) of eating disorder symptoms (shape concerns, weight concerns, binge eating episodes, episodes of compensatory behaviors, urges to eat or compensate) for five days (five signal-contingent measurements and additional event-contingent assessments) | 0 weeks, 12 weeks | 
| Changes in eating-disorder-related daily difficulties | The Clinical Impairment Assessment Questionnaire (CIA; Bohn et al., 2008) consists of 16 items answered on a 4-point Likert scale. The overall score ranges from 0 to 48. Higher values indicate a higher level of clinical impairment. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in comorbid depressive symptoms | The Patient Health Questionnaire (PHQ-9; Kroenke et al., 2001) consists of 9 items answered on a 4-point scale. The overall score ranges from 0 to 27. Higher values indicate a higher level of depressive symptomology. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in comorbid anxiety symptoms | The General Anxiety Disorder Scale (GAD-7; Spitzer et al., 2006) consists of 7 items answered on a 4-point scale. The overall score ranges from 0 to 21. Higher values indicate a higher level of anxiety symptoms. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in well-being | The World Health Organization Well-Being Index (WHO-5; Topp et al., 2015) consists of 5 items answered on a 6-point scale. The overall score ranges from 0 to 100. Higher values indicate a higher level of well-being. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in self-esteem | The Rosenberg Self-Esteem Scale (RSES; Roth et al., 2008) consists of 10 items answered on a 4-point scale. The overall score ranges from 0 to 30. Higher values indicate a higher level of self-esteem. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in work capacity | The iMTA Productivity Cost Questionnaire (iPCQ; Bouwmans et al., 2015) consists of 12 items grouped in general questions about paid work and questions about productivity losses in paid and unpaid work. The questionnaire captures the missed work time (paid and unpaid) in hours for short-term absence and calendar days for long-time absence and the hours of lost productivity due to presenteeism. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in emotion regulation frequencies | The Heidelberg Form for Emotion Regulation Strategies (HFERST; Izadpanah et al., 2019) consists of 28 items answered on a 5-point scale. For each of the eight emotion regulation strategies (rumination, reappraisal, acceptance, problem solving, suppression of emotional expression, suppression of emotional experience, avoidance, social support), a score ranging from 1 to 5 can be calculated. Higher values indicate a higher frequency of emotion regulation strategy endorsement. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in emotion regulation difficulties | The Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004) consists of 36 items answered on a 5-point scale. The overall score ranges from 36 to 180. Higher values indicate a higher level of emotion regulation difficulties. | 0 weeks, 6 weeks, 12 weeks | 
| Changes in everyday emotion regulation | Ecological momentary assessment (EMA) of affect, emotion regulation strategies and difficulties for five days (five signal-contingent measurements, and additional event-contingent assessments) | 0 weeks, 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ecological Momentary Assessment, Internet-based Intervention, Randomized Controlled Trial