Last month, I argued that patients experience one health system rather than separate government ministries. A decision on taxation affects access to care. Medicine procurement influences public confidence. Health financing shapes treatment choices. Patients do not experience these issues separately. They experience them together.
That discussion leads naturally to another question. How should governments recognise harm during a health-system crisis?
Recent public statements concerning medicine shortages and mortality have raised an important scientific and policy question. The question is not whether evidence matters. It does. Nor is it whether governments should rely on facts rather than speculation. They should. The real question is what counts as evidence when a health system is under pressure.
Health Policy and Systems Research has long recognised that health-system failure is rarely revealed by a single statistic. Harm often begins quietly. Treatments are interrupted. Medicines become unavailable. Patients postpone care. Health workers improvise. Families spend more out of pocket. Trust begins to erode. By the time mortality statistics begin to change, the health system may already have been signalling distress for months.
This distinction lies at the heart of the current debate. It is also where science has the greatest contribution to make.
The Minister’s Statement
Against this background, the Assistant Minister of Health recently stated that government had found no evidence linking medicine shortages directly to patient deaths. The statement reflects an important principle of scientific reasoning. Governments should not attribute deaths to medicine shortages without credible evidence. Public confidence depends on decisions grounded in careful investigation rather than assumption.
The statement, however, also raises an important methodological question. Does the absence of evidence demonstrating a direct causal relationship between medicine shortages and recorded mortality necessarily mean that medicine shortages have caused no harm?
Health Policy and Systems Research suggests that the answer is more nuanced. Health systems are complex adaptive systems in which outcomes rarely arise from a single cause acting in isolation. A patient’s health is shaped by a chain of interconnected events involving diagnosis, medicine availability, health-worker capacity, referral systems, financing and continuity of care. Weakness in any one part of that chain can influence the eventual outcome.
Researchers therefore distinguish between absence of evidence and evidence of absence. As Altman and Bland (1995) observed, failing to demonstrate a relationship is not the same as demonstrating that no relationship exists. That distinction provides the starting point for understanding what the international evidence shows.
What the International Evidence Shows
International research has consistently shown that medicine shortages are far more than pharmaceutical supply problems. They are recognised as health-system risks that affect the quality, continuity and safety of patient care. While shortages may contribute to increased mortality in some circumstances, the evidence demonstrates that their consequences are usually broader, more gradual and more complex than a single mortality statistic can capture.
The World Health Organization identifies uninterrupted access to essential medicines as one of the six core building blocks of a functioning health system because medicines underpin effective service delivery, clinical decision-making and public confidence (WHO, 2007). Building on this, de Savigny and Adam (2009) argue that health systems should be understood as interconnected systems in which disruption in one component inevitably affects others. A medicine shortage is therefore not simply a procurement problem; it is a signal of wider system stress.
The Lancet Commission on High-Quality Health Systems reaches a similar conclusion. Kruk and colleagues (2018) argue that health-system performance should be judged not only by access to services but by whether patients receive timely, safe, effective and trusted care. Continuity of treatment is therefore as important as the availability of treatment.
Evidence specific to medicine shortages reinforces this broader perspective. Systematic reviews by Fox and McLaughlin (2018) and Acosta and colleagues (2019) consistently associate medicine shortages with treatment interruption, medication substitution, avoidable complications, increased out-of-pocket expenditure, greater pressure on health professionals and poorer patient experiences. Although studies vary in their findings on direct effects on mortality, they overwhelmingly conclude that shortages generate measurable clinical, economic and humanistic harm.
This conclusion is also reflected in patient safety research. The Institute of Medicine argued that high-quality health systems should identify risks before they result in avoidable harm rather than simply record adverse outcomes after they occur (Institute of Medicine, 2001). Collectively, this body of evidence suggests that medicine shortages should be understood not merely as supply-chain failures, but as indicators of health-system vulnerability requiring timely stewardship and policy action.
Looking Beyond Mortality: What Counts as Evidence?
The international evidence raises an important question. If medicine shortages can cause harm without immediately affecting mortality, what should governments regard as evidence?
Health Policy and Systems Research offers a broader answer than mortality statistics alone. Health Policy and Systems Research is different to clinical research, that often aims to find direct cause-effect relationships. Health Policy and Systems Research looks at how institutions, policies and governance arrangements affect health outcomes. It asks how health systems function in practice and how the interactions between different elements of the system shape the care that patients receive (Gilson, 2012; Sheikh et al., 2011).
From this perspective, mortality is a lagging indicator. It records an outcome after a chain of events has already unfolded. By contrast, medicine availability, treatment continuity, delayed care, patient experience and financial hardship are leading indicators. They provide early evidence that a health system is under strain and allow governments to intervene before adverse outcomes become irreversible.
This distinction is familiar across many sectors. Repeated equipment failures are investigated by aviation authorities before an aircraft crashes. Before a bridge falls down , engineers fix weaknesses in a structure . Disease surveillance response by public health officials before hospitals are overwhelmed. Effective governance depends on recognising risk early rather than waiting for catastrophe.
The same principle applies to health systems. Governments may not yet be able to demonstrate that a particular medicine shortage directly caused a particular death. That level of proof often requires detailed clinical investigation and robust epidemiological analysis. However, they do not need to wait for such evidence before responding to credible indications that medicines are unavailable, treatment is being interrupted or patients are struggling to access care. The purpose of evidence is not simply to confirm failure. It is to prevent it.
Measuring Harm Before It Becomes Catastrophe
If mortality is only one indicator of health-system performance, the next question is straightforward: what should governments measure during medicine shortages?
Health Policy and Systems Research encourages governments to monitor the conditions that increase the likelihood of harm rather than waiting for harm to become visible. The objective is not simply to document failure, but to detect emerging risks early enough for corrective action to be taken. This is core to stewardship and resilience of health systems (WHO, 2021).
Several indicators are particularly important. The first is the frequency and duration of medicine stock-outs, which provide an early measure of the reliability of procurement and supply systems. The second is treatment continuity. For patients living with chronic conditions such as hypertension, diabetes, HIV infection, epilepsy and cancer, interruptions in treatment may not produce immediate mortality, but they can accelerate disease progression, increase complications and reduce quality of life (Fox and McLaughlin, 2018; Acosta et al., 2019).
Governments should also monitor medicine substitution, delayed appointments, household out-of-pocket expenditure and patient experience. Together, these indicators reveal how shortages affect clinical practice, financial protection and public confidence in the health system. As Gilson has argued, trust is not merely a desirable outcome of effective governance; it is one of the conditions that enables health systems to function effectively.
Viewed together, these measures provide a far richer understanding of health-system performance than mortality statistics alone. They allow governments to recognise vulnerability, strengthen system resilience and intervene before service disruption develops into avoidable harm.
A Better Question for Botswana
The recent public discussion on medicine shortages presents Botswana with an opportunity to strengthen, rather than polarise, evidence-informed health policymaking. The issue is not whether governments should rely on evidence they must. Nor is it whether claims linking medicine shortages to mortality require careful scientific investigation they do. The broader challenge is ensuring that the evidence collected is sufficiently comprehensive to recognise risks before they become irreversible harm.
As Botswana continues to strengthen primary healthcare, improve medicines governance and advance universal health coverage, this debate should encourage investment in stronger medicines surveillance, routine monitoring of treatment continuity, patient safety, stock-out reporting and health-system intelligence. These are not simply technical functions. They are essential components of stewardship because they enable governments to detect emerging risks, respond proportionately and learn from experience before patients suffer avoidable harm.
Ultimately, the strongest health systems are distinguished not by how well they explain tragedy after it has occurred, but by how effectively they recognise risk and prevent it. That is the enduring contribution of Health Policy and Systems Research-and perhaps the most important lesson this debate offers Botswana.