What key conditions and mechanisms generate health inequalities research in different contexts? Study protocol for two realist explanatory case studies

Evidence on health inequalities has grown in recent decades, however, the capacity to generate health inequalities research is uneven, worldwide. A recent bibliometric analysis found notable inequalities of the global production of health inequalities scientific research across countries. What determines the capacity to produce high volumes of health inequalities scientific research, in different settings? What mechanisms are involved? To answer these questions requires in-depth knowledge on the health inequalities research production process, in different settings. We plan to conduct two realist explanatory case studies, to understand why and how particular settings (e.g. the United Kingdom and the city of Barcelona) have generated high volumes of health inequalities research over past decades, and identify the potential key contextual conditions and causal mechanisms involved. This study protocol outlines the rationale and methodology involved, highlights the strengths and limitations of the approach, and provides guidance on how to overcome certain operational challenges and ensure validity of research findings. Valuable learning may be derived from these case experiences, with implications for research, policy and practice. This work can serve as a tool for researcher and planners to guide the development of further case studies to evaluate health inequalities research capacities in other settings.