IN A NUTSHELL
Editor's Note 
This article puts under a critical lens some findings from the Global Burden of Disease 2023 report, whereby the uncertain attribution of COVID-19 deaths, YLLs and the problem of the “frontier” reference, and the arbitrary 70-year threshold are pointed out

By Juan Garay

Founder and Co-chair of SHEM. Professor of Global health. Lead of the Valyter ecovillage.  Valyter.es  

Rethinking Global Health Metrics Beyond the Frontier

A Response to the GBD 2023 Mortality Report

 

The Global Burden of Disease 2023 report represents an extraordinary global effort to compile, harmonize, and analyse mortality data across countries and decades. Its contribution to understanding health progress is invaluable. Yet, the report’s findings—especially those concerning deaths attributed to COVID-19, the use of Years of Life Lost (YLL) relative to the lowest observed mortality rates, and the reliance on the 70-year threshold for “preventable deaths”—require careful reconsideration.

Uncertain attribution of COVID-19 deaths

The report notes that COVID-19 ranked as the world’s leading cause of death in 2021 before falling to 20th place by 2023. However, these rankings are constrained by major uncertainties in data quality and attribution. During the pandemic, testing capacity, diagnostic coding, and death certification varied widely across countries. Official counts therefore reflect not only viral lethality but also the reach and reliability of national surveillance systems.

Equally important, many deaths during 2020–2022 arose indirectly from health-system disruption, economic hardship, and delayed care for chronic conditions. WHO estimated approximately 14.8 million excess deaths in 2020–2021, nearly three times the number of officially reported COVID deaths, underscoring the magnitude of indirect losses. Analyses based solely on cause-coded deaths should therefore be complemented by age-standardised excess mortality and indicators of service disruption to capture the full human cost of the pandemic, including the effects of political and economic responses.

YLLs and the problem of the “frontier” reference

The GBD’s YLL metric measures losses against a “frontier” life table derived from the lowest age-specific mortality rates observed globally. This facilitates comparability but assumes that the best-performing populations define a universal goal. In reality, those frontier rates are sustained in contexts that depend on ecological and economic conditions not feasible or sustainable worldwide.

According to the WHO Constitution, global health policy should aim for “the attainment by all peoples of the highest attainable standard of health.” This implies striving toward best feasible and sustainable levels of health for all, not replicating conditions achievable only through intensive consumption or unequal distribution of resources. Measuring losses relative to realistic and sustainable reference standards transforms YLLs from abstract deficits into ethically grounded indicators of inequity.

The arbitrary 70-year threshold

The probability of dying before age 70 (70q0) remains a core GBD indicator of “premature” mortality. While operationally convenient, this threshold is arbitrary and increasingly obsolete. The best feasible and sustainable life expectancy today is estimated around 77.5 years, not 70. Limiting the definition of preventable deaths to those occurring before 70 therefore underestimates the true scope of avoidable mortality and conceals inequalities emerging in later adulthood.

A more consistent approach is to define preventable deaths as those exceeding feasible and sustainable age-specific mortality rates. This aligns with WHO’s constitutional goal and allows for continuous measurement of progress across the life course.

Measuring equity: the Relative Burden of Health Inequity

A complementary indicator—the Relative Burden of Health Inequity (RBHiE)—expresses the proportion of all deaths exceeding feasible and sustainable mortality references. This measure provides a clear and comparable assessment of how far populations remain from the attainable benchmark of health equity. Unlike 70q0 or frontier-based YLLs, RBHiE directly reflects progress toward the WHO objective of the best feasible level of health for all.

Toward a fairer global health measurement paradigm

The GBD’s technical sophistication and transparency are commendable, but its next phase should integrate excess-mortality data, feasible and sustainable reference standards, and equity-based indicators such as RBHiE. Only then can the global health community move from describing disease burdens to assessing humanity’s collective distance from a just and sustainable standard of health.

 

References

WHO Constitution (1946). Preamble: the attainment by all peoples of the highest attainable standard of health

WHO (2022). Global excess deaths associated with COVID-19 (2020–2021)

GBD 2023 Mortality and Causes of Death Collaborators. Lancet (2025)

Sustainable Health Equity Movement (SHEM). Atlas of Global Health Inequity: Toward Feasible and Sustainable Reference Standards (2024)

 

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By the same Author on PEAH: see HERE