Importance: In the US, most postmarket medical device safety data are obtained through adverse event reports that are submitted to the US Food and Drug Administration (FDA)'s Manufacturer and User Facility Device Experience (MAUDE) database. Adverse event reports are classified by the reporter as injury, malfunction, death, or other. If the device may have caused or contributed to a death, or if the cause of death is unknown, the FDA requires that the adverse event be reported as a death.
Objective: To determine the percentage of medical device adverse event reports submitted to the MAUDE database that were not classified as death even though the patient died.
Design, setting, and participants: In this study, a natural language processing algorithm was applied to the MAUDE database, followed by manual text review, to identify reports in the injury, malfunction, other or missing categories that included at least 1 term that suggested a patient death, such as patient died or patient expired, from December 31, 1991, to April 30, 2020, for any medical device.
Exposures: Manual review of a random sample of 1000 adverse event reports not classified as death and of selected reports for 62 terms that are associated with deaths but were not classified as death.
Main outcomes and measures: Percentage of adverse event reports in which the patient was said to have died in the narrative section of the report but the reporter classified the report in a category other than death.
Results: The terms in the natural language processing algorithm identified 290 141 reports in which a serious injury or death was reported. Of these, 151 145 (52.1%) were classified by the reporter as death and 47.9% were classified as malfunction, injury, other, or missing. For the overall sample, the percentage of reports with deaths that were not classified as deaths was 23% (95% CI, 20%-25%), suggesting that approximately 31 552 reports in our sample had deaths that were classified in other categories. The overall percentage of missed deaths, defined as the percentage of deaths that were classified in other categories, was 17% (95% CI, 16%-19%).
Conclusions and relevance: Many of the findings of this study suggest that many medical device adverse event reports in the FDA's MAUDE database that involved a patient death are classified in categories other than death. As the FDA only routinely reviews all adverse events that are reported as patient deaths, improving the accuracy of adverse event reporting may enhance patient safety.