Promoting transferability: Insights from economic evaluations of public health interventions to tackle malaria in central Senegal

Health economic evaluation seeks to guide priority setting by generating evidence on the relative efficiency of alternative policy choices. Yet, the volume and quality of economic evaluations are insufficient to inform the vast array of policy choices, especially in low- and lower-middle-income countries. This thesis aims to inform policy choices regarding strategies to tackle malaria and to improve methods to transfer economic evaluation evidence across contexts. A bibliometric analysis of the applied economic evaluation literature frames the thesis. Two economic evaluations were conducted sequentially alongside two cluster-randomized controlled trials in approximately the same population of over 500,000 people in four districts of central Senegal. The first evaluation explored the financial and economic costs of equipping community health workers to deliver seasonal malaria chemoprevention (SMC) door-to-door to children under 10 years of age. It revealed substantial economies of scale, with the largest primary healthcare facility catchment areas (by population) incurring the lowest average costs per child treated. The second evaluation assessed the costs and cost-effectiveness of several multi-component, geographically targeted, malaria strategies in a low transmission context. Building on the analysis of SMC, the data collected in the second trial was used to develop and populate a simple, transparent, flexible, and intuitive cost model, which projects how the costs of four interventions may be expected to vary outside the study setting, in other contexts, and with certain changes to the interventions themselves, as well as with input prices and epidemiology. Drawing on the two economic evaluations and a critical review of wide-ranging literatures relevant to transferability, the thesis concludes by proposing guidance for the design and conduct of economic evaluations alongside trials or pilots in ways that promote transferability. In particular, it recommends efforts from the outset of the evaluation to identify and narrow the “transferability gap” between planned implementation within the trial or pilot and the intended decision contexts.