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Official development assistance (ODA) accounts for the majority of humanitarian and development assistance in the world's most vulnerable countries and has played a pivotal role in advancing global health. We aimed to comprehensively evaluate the impact of ODA funding on mortality across the past two decades, and to project the potential consequences of current defunding trends.
Methods
We conducted an integrated retrospective evaluation and forecasting analysis using longitudinal panel data from 93 low-income and middle-income countries (LMICs). First, we estimated the association between ODA per-capita funding and mortality outcomes from 2002 to 2021 using a two-ways fixed-effects multivariable Poisson regression model with robust standard errors, adjusted for all relevant demographic, socioeconomic, and health-system covariates. We then assessed age-specific and cause-specific effects, performing extensive sensitivity and triangulation analyses to test the robustness and causal interpretation of results. Finally, we integrated the retrospective impact estimates into validated country-level microsimulation models to forecast mortality under three defunding scenarios up to 2030: a business-as-usual trajectory, a severe defunding scenario, and a mild defunding scenario.
Findings
Higher ODA funding levels were associated with a 23% reduction in age-standardised all-cause mortality (rate ratio [RR] 077; 95% CI 070"085) and a 39% reduction in under-5 mortality (061; 049"075). ODA funding was associated with large mortality declines in major communicable diseases: 70% for HIV/AIDS (RR 030; 95% CI 024"039), 56% for malaria (044; 035"056), 56% for nutritional deficiencies (044; 030"065), and 54% for neglected tropical diseases (046; 036"059). Significant reductions were also observed in mortality from tuberculosis, diarrhoeal diseases, lower respiratory infections, and maternal and perinatal causes. Forecasting analyses projected that ongoing reductions in ODA funding could, under a severe defunding scenario, result in 226 million (95% uncertainty interval [UI] 163"293) additional deaths across all ages by 2030, including 54 million (41"68) among children younger than 5 years. Under a mild defunding scenario"defined as a continuation of current downward trends"the projected excess deaths would be 94 million (95% UI 62"126) overall and 25 million (18"32) among children younger than 5 years.
Interpretation
ODA funding has played a decisive role in reducing preventable mortality across LMICs over the past two decades, and the abrupt withdrawal of this support threatens to cause millions of avoidable deaths, reversing decades of progress in global health.