Commonly cited approaches to reducing health inequalities: a call for more clarity around their definition and underlying assumptions.

Addressing health inequalities is an international priority. Various approaches have gained popularity in the academic literature and policy-making documents. However, there has been a lack of progress in tackling health inequalities. We outline the main characteristics and principles of five commonly cited approaches: asset-based, place-based, upstream, systems-based and proportionate universalism. We examine how these approaches are described in the literature and the logic by which they are thought to tackle health inequalities.There was variation in how each approach was described and interpreted. The logic behind how the approaches could improve population health was clearly articulated but often under-developed with respect to health inequalities. Although rarely acknowledged explicitly, it was implied that these approaches seek to reduce health inequalities through focussing on more socially disadvantaged sub-groups in a population, identifying the most impactful intervention levers and/or working to minimise stigma and minimise inequalities in access and uptake of interventions. More attention should be paid to the important principles, features and underlying logic of these approaches in relation to health inequalities to better understand the potential supports and barriers to their success. This will support those working to implement them to do so in ways that are sensitive to local and contextual specificities.