A health system encompasses all organizations, institutions, resources, and actions whose primary purpose is to promote, restore, or maintain health. The WHO framework describes six building blocks: service delivery, health workforce, health information systems, medical products, financing, and governance. Financing mechanisms—general taxation, social health insurance, private insurance, out-of-pocket payment—determine who bears health costs and who is covered. Universal health coverage (UHC) aims to ensure all people obtain needed health services without financial hardship, measured along three dimensions: population covered, services included, and proportion of costs covered. Out-of-pocket spending drives millions into poverty annually and is the primary barrier to UHC in low-income settings.
Compare the financing and coverage structures of three health systems (e.g., UK NHS, US mixed system, Rwanda community-based insurance) using the WHO building blocks framework. Evaluate each against UHC dimensions and identify the key tradeoffs each makes.
A health system is not just a collection of hospitals and clinics — it is the entire organized effort of a society to produce health. From your background in social determinants of health, you understand that most inputs to population health (housing, nutrition, education, income) lie outside the formal health system. But the health system is the part deliberately designed to manage illness and prevent disease, and understanding how it is structured and financed explains much of the variation in health outcomes between countries with similar disease burdens and similar wealth.
The WHO framework organizes health systems into six building blocks: (1) service delivery, (2) health workforce, (3) health information systems, (4) medical products and technologies, (5) financing, and (6) governance and leadership. These are deeply interdependent — excellent financing accomplishes nothing if there is no trained workforce, and excellent clinical training achieves little without governance structures that deploy workers where the burden is highest. The building blocks are useful diagnostically: when a health system underperforms, you can ask which block is failing. Is the problem that services don't exist? That the workforce is too small or maldistributed? That information systems cannot track outcomes? That governance is fragmented or corrupt? Different diagnoses require different interventions.
Financing deserves special attention because it determines who pays and who is protected. The four main mechanisms are: general taxation (government funds services for all citizens — the UK NHS model), social health insurance (mandatory payroll contributions pooled into a non-profit fund — Germany, Japan, South Korea), private voluntary insurance (risk-pooling through market competition), and out-of-pocket payment (direct payment at the point of care). These mechanisms differ fundamentally in equity. General taxation and social insurance spread financial risk across the entire population, so sick people do not bear the full cost of their illness. Out-of-pocket spending concentrates costs on those who are sick and often poor, and is the primary mechanism driving medical impoverishment globally — a single hospitalization can wipe out a family's savings in low-income settings with weak financial protection.
Universal health coverage (UHC) is not a system design but a goal: that every person receives needed health services without suffering financial hardship. The WHO measures UHC along three dimensions: *who* is covered (population breadth), *what services* are included (benefit package breadth), and *what proportion of costs* are covered (depth of financial protection). Most low-income countries face deficits on all three. Most high-income countries achieve population coverage but vary on depth — cost-sharing through deductibles and copayments still causes significant financial hardship in systems nominally providing universal access. The practical challenge is that expanding all three dimensions simultaneously is expensive, forcing tradeoffs: covering everyone for a narrow essential package, or covering fewer people for a broader range of services. Understanding these tradeoffs requires exactly the kind of disease burden and prevention-level analysis that your prior courses have built.