Assessing the quality of cause-of-death reporting before and during the COVID-19 pandemic

This study assessed the quality of cause-of-death reporting in the United States before and during the COVID-19 pandemic. We used the selection rate and the adjusted odds ratio (aOR) to analyze each cause identified by the National Center for Health Statistics as unsuitable for the underlying cause of death (UCOD). The selection rate was defined as the proportion of deaths with mention of a particular unsuitable UCOD on the death certificate where that cause was ultimately selected as the UCOD. Out of 36 unsuitable UCODs, 33 exhibited a significant decline in selection rates from 2019 to 2021. However, when deaths with mention of COVID-19 on the death certificate were excluded, only 19 causes revealed a significant decline. In analyses that controlled for the age of decedents, aORs in 2021 were significantly lower compared with 2019 for 26 causes, and this number decreased to 17 causes in analyses that excluded COVID-19-related deaths. In conclusion, the overall quality of COD reporting improved during the COVID-19 pandemic, attributable mainly to the fact that over one-tenth of the deaths were related to COVID-19. Yet, for deaths that did not involve COVID-19, improvements in the quality of COD reporting were less prominent for certain causes.