Improving health equity through theory-informed evaluations: A look at housing first strategies, cross-sectoral health programs, and prostitution policy

The emergent realist perspective on evaluation is instructive in the quest to use theory-informed evaluations to reduce health inequities. This perspective suggests that in addition to knowing whether a program works, it is imperative to know ‘what works for whom in what circumstances and in what respects, and how?’ (Pawson & Tilley, 1997). This addresses the important issue of heterogeneity of effect, in other words, that programs have different effects for different people, potentially even exacerbating inequities and worsening the situation of marginalized groups. But in addition, the realist perspective implies that a program may not only have a greater or lesser effect, but even for the same effect, it may work by way of a different mechanism, about which we must theorize, for different groups. For this reason, theory, and theory-based evaluations are critical to health equity.