Comparison of COVID-19 mortality estimates from Centers for Disease Control and Prevention wide-ranging ONline data for epidemiologic research and the global burden of disease study in the United States, 2020–2023

Accurate estimation of cause-specific mortality is essential for public health decision-making, yet differences in surveillance methodologies may yield divergent results. This study compared the United States COVID-19 mortality estimates from 2020 to 2023 using the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research (CDC WONDER) and the Global Burden of Disease (GBD) study. COVID-19 deaths were identified using ICD-10 code U07.1, and crude mortality rates and percent change were calculated. Across the study period, GBD reported 1,207,595 deaths compared with 1,004,208 deaths in CDC WONDER underlying-cause data, representing 16.8% higher cumulative mortality. Discrepancies were greatest in 2020–2021 but narrowed over time. When CDC WONDER data including underlying and contributing causes were examined, mortality estimates remained lower than GBD early in the pandemic but exceeded GBD estimates in 2022–2023. Both datasets demonstrated similar temporal declines in mortality. These differences reflect how each system ascertains, codes, and handles the cause of death. Registration-based and modeled estimates of COVID-19 mortality are therefore not directly interchangeable, and the choice of source can change conclusions about the scale of the pandemic and the share of excess mortality attributed directly to COVID-19.