Solidarity in global health is often invoked as an ethical imperative to guide responses to global health challenges. Its meanings and practices across diverse contexts, however, remain under-explored. Deepening an understanding of how solidarity is conceptualised, enacted and perceived by a diverse array of actors within the global health ecosystem is crucial to advancing meaningful and measurable application of this commitment in global health.

This qualitative study uses interpretive research methodology to explore perspectives on solidarity among key global health stakeholders: community-level leaders in civil society organisations working on global health issues; research institute directors in the Global South; and individuals with experience of funding decision-making with major global health funding and agenda setting organisations (‘global health influencers’). Data will be gathered through semi-structured interviews and analysed using inductive and deductive reflexive thematic analysis, to identify patterns and differences in how these global health stakeholders recognise and define solidarity or its absence in their day-to-day work, while remaining attentive to conceptual tensions, participant interpretations of solidarity that may be unfamiliar to our team, and our role as researchers in shaping what we register and emphasise as significant in our reporting of findings.

Ethics approval was obtained from the Western University Health Sciences Research Ethics Board (HSREB) in Ontario, Canada # 2024-123965-87873 and the Ethics Committee for the Humanities, University of Ghana # ECH 163/23–24 and University of Oxford, Oxford Tropical Research Ethics Committee (OxTREC) waiver dated 10 April 2024. Study results will be submitted for peer-reviewed publication. Results will also be summarised in an open access report and presented at various stakeholder meetings and in online webinars.

The final protocol was registered with Open Science Framework on 28 October 2023. View only link: https://osf.io/gryp5/?view_only=8baff435a35847f09a342408d38ee35b.

The long-term success of metabolic and bariatric surgery (MBS) depends largely on adherence to health-promoting behaviour following MBS. Especially, adherence to healthy dietary behaviour in line with guidelines appears to be of the utmost importance. The primary objective of the present study is to evaluate the effect of adherence to dietary behaviour recommendations and the percentage of total weight loss (%TWL) after MBS. Adherence is hypothesised to have a positive influence on the %TWL, 24 months after MBS. Furthermore, we investigate the association of various sociodemographic, organisational, psychological and behavioural factors prior to and after MBS and their effect on %TWL.

The present study is a single-centre observational, prospective, longitudinal cohort study conducted in Germany. Data are collected at nine measurement points (T0: 4 weeks prior to MBS; T1: 2 weeks after MBS, T2: 5 weeks after MBS; T3: 3 months after MBS; T4: 6 months after MBS; T5: 12 months after MBS; T6: 18 months after MBS; T7: 24 months after MBS; and T8: 36 months after MBS). Adherence to dietary behaviour recommendations is assessed using the Dietary Behavior Inventory-Surgery (DBI-S). N=325 patients applying for MBS will be included in the study. A regression analysis approach is chosen to answer the primary research question. The primary outcome %TWL is regressed at T7 (24 months after MBS) in a causal analysis on dietary adherence (DBI-S score) at T3–T7, with the covariates age, gender, marital status, educational attainment, employment status, Patient Health Questionnaire-4 score and body mass index at T0 and MBS method at T1. Stepwise hierarchical regression analyses are performed and analysed for significant model differences using ² difference tests. Effect sizes are estimated by R². Group differences are analysed using t-tests and Analyses of variance (ANOVAs). Bivariate correlations of continuous variables are examined using regression/correlation analyses.

The Ethics Committee of the Medical Faculty of the University of Essen-Duisburg has approved the conduct of the study (24-11969-BO). Results will be disseminated through manuscripts in clinical/academic peer-reviewed journals, presentations at academic conferences and communications with partners, participants and other stakeholders. Key findings will also be published in lay language on a publicly accessible website and disseminated via various (social) media channels.

The study has been prospectively registered on 8 October 2024 in the German Clinical Trials Register (DRKS00034888).