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

Brief Summary

Detailed Description

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.

Primary Outcomes

Secondary Outcomes

• Changes in global eating psychopathology(0 weeks, 6 weeks, 12 weeks)
• Changes in eating-disorder-related daily difficulties(0 weeks, 6 weeks, 12 weeks)
• Changes in self-esteem(0 weeks, 6 weeks, 12 weeks)
• Changes in well-being(0 weeks, 6 weeks, 12 weeks)
• Changes in the weekly frequency of binge eating episodes, compensatory behavior, and regular eating(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 comorbid depressive symptoms(0 weeks, 6 weeks, 12 weeks)
• Changes in everyday eating disorder symptoms(0 weeks, 12 weeks)
• Changes in comorbid anxiety symptoms(0 weeks, 6 weeks, 12 weeks)
• Changes in emotion regulation frequencies(0 weeks, 6 weeks, 12 weeks)
• Changes in emotion regulation difficulties(0 weeks, 6 weeks, 12 weeks)
• Changes in work capacity(0 weeks, 6 weeks, 12 weeks)
• Changes in everyday emotion regulation(0 weeks, 12 weeks)