Toward a unified theoretical model of bulimia nervosa: protocol for a systematic review and synthesis of existing theories

Abstract Background Bulimia nervosa is a severe mental disorder associated with several physical and mental health complications. The aim of this review is to provide an overview of existing theoretical models regarding the development and maintenance of bulimia nervosa. A second aim is to develop a synthesis to allow for a more complete understanding of bulimia nervosa, which may help to develop and refine interventions in the future. Methods PsycInfo, PubMed, PSYNDEX, Scopus, and Google Scholar will be searched for studies presenting models of bulimia nervosa. Topic modeling will be used to gain initial insights into related factors. Additionally, two independent expert reviewers will screen the literature and select models of bulimia nervosa as well as associated datasets for additional empirical analyses. In the case of discrepancies, a third reviewer will be consulted. The similarities between the identified models of bulimia nervosa will be summarized in a narrative synthesis. Depending on the number of identified models and available datasets, models will be tested using existing datasets. Discussion The review seeks to summarize existing models regarding the development and maintenance of BN. The results could be used as a starting point for developing adequate models, testing these models, and subsequently using them to inform evidence-based intervention programs in the future. Systematic review registration This systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 30.09.2024 (CRD42024581179).