A conceptual review of migration trajectories, uncertainty and health

Abstract Background Migration trajectories are complex, non-linear movements, including periods of immobility, secondary migration, return and psychosocial changes. A key feature of these trajectories is uncertainty, resulting from incomplete place-based knowledge and an unpredictable future. We reviewed how migration trajectories and related uncertainties have been conceptualised and operationalised in health-related research. Methods We systematically searched Medline, Embase, Web of Science, and Global Index Medicus. After duplicate screening, we extracted information on concept definitions, operationalisations and links to health. Uncertainty factors were mapped followed by a narrative synthesis. Results Of 3836 titles, we synthesised 66 articles which mostly focused on forced migrants in high-income countries. Study designs, concept definitions and operationalisations varied substantially. Phase models outlining consecutive migration stages were frequently applied, with some also considering non-linearity of trajectories. Uncertainty was mostly related to legal status, followed by uncertainty of the future, ‘general’ uncertainty of migration processes, and uncertainty of social relations. Fewer studies considered uncertainty of economic, healthcare, and societal factors. The majority of studies linked uncertainty to adverse mental health outcomes. Conclusions Our review demonstrates multifaceted uncertainties along migration trajectories, with studies repeatedly showing negative psychological impacts of legal uncertainty. Current concepts fall short in generating health-related knowledge that links theory with pathways to health at the intersection of contexts, migration regimes, and temporal aspects of migration. Concepts moving beyond uncertainty as a hazard and improved methods for studying uncertainty are required. Research is also needed to assess how migration regimes amplify uncertainty for migrants while reducing (unwanted) uncertainty for state actors. Key messages • Uncertainty is a defining feature of migration, but links to health are under-researched. • Advancing concepts and methods for studying uncertainty across migration trajectories is required given the role of mobility regimes.