transport networks offers a promising line of inquiry.<sup>22</sup> Further research could use these and other inputs to understand the drivers of variation in caseloads. As an alternative, health system policy could move towards allocating more resources to locations where caseloads are already higher, rather than applying rules that do not account for spatial density (such as “one health facility for every 3,000 population”).

The second crisis is the misallocation that arises because of the weak correlation between provider competence and caseloads. Put simply, some countries are spending millions of dollars training competent providers, but at the caseload levels we observed, simulations using queuing theory suggest they are often spending as much as 75% of their time not seeing patients. We provide a novel measure of the quality implications of this misallocation, and we find that in some countries the magnitude of these inefficiencies exceeds the potential gains from training nearly every existing PHC provider to the competence level of a local doctor.

Whether the kind of hypothetical reallocations we presented here are actually desirable or feasible is a harder question. To begin with, understanding where to place the most competent providers requires an open debate about health system priorities: Is it preferable to place a highly competent provider in a slum, where they will see many more poor people, or in a sparsely populated rural region where there may not be any other options? To add to this challenge, as we have seen in previous work, the competence of PHC providers is not well-predicted by their qualifications, so even among doctors and nurses there is wide variation in proficiency. Administrators cannot make efficient allocation decisions unless there is a concerted effort to measure and document medical competence at the individual level using direct assessments that go beyond formal qualifications.

In summary, we provide evidence that the current consensus of a _general_ human resources crisis in health is misleading. Under conditions of general scarcity, policy options are limited to increasing capacity. Our data suggest that general scarcity is almost never a binding constraint at the system level. Instead, we argue that the problem is a more nuanced one of variation in caseloads and misallocation of competent providers. There is excess capacity in every health system already, even among high-competence providers: We find that human resources are simply not in the same places as patients are.

In part because human capital investments are already underutilized, we find that increasing capacity through upskilling is generally a _less_ effective approach in contexts where improved allocation could produce quality improvements. Finally, we show that in very low-performing countries, there are much more serious underlying issues. These countries seem to have extremely limited capacity to consistently train competent medical providers, so neither allocative improvements nor increased training levels would produce meaningful quality improvements with the status quo institutions. Our hope is that the results presented here will open up the conversation and allow us to more precisely benchmark and suggest policy options for countries that are more tailored to their specific needs.

**14/30**