Top-to-Bottom Approach

This approach is used in situations where access to communities is restricted either due to conflict/security issues or restrictions imposed by governments or implementing partners. This approach is also favoured when organizations have limited resources to map individual communities/villages. In Chad, the health system has a pyramidal structure where health facilities at each level perform specific functions mandated to them. The highest level of the pyramid is a national level institution, followed by intermediary levels (regional health institutions, district hospitals) and peripheral level (health centres). These different level institutions can be grouped to represent the catchment area of any health intervention or program, as was demonstrated when MSF utilized these divisions to inform and visualize the scope of their work in the country. This database was easier to create and was less resource intensive. However, these databases were more difficult to maintain as these sub-level boundaries changed rapidly and inconsistently. Attempts to provide finer detail to such catchment areas would require recruitment of staff on the ground. These top-to-bottom catchment area databases lack precision and thus, are mainly used for data visualization, scoping, or monitoring purposes. A diagrammatic representation of this pyramidal health system boundary structure is shown in Figure 4.

Figure 4: Health boundary pyramidal structure showcasing the Top-to-Bottom approach (Adapted from National Health Statistics, MoH, CHAD).10