Assessing the National Electronic Injury Surveillance System — Cooperative Adverse Drug Event Surveillance Project — Six Sites, United States, January 1–June 15, 2004

Adverse drug events (ADEs) occur when therapeutic drugs have injurious effects; current systems for conducting national ADE surveillance are limited, and current national estimates of ADE incidence are problematic. In 2003, CDC, in collaboration with the Consumer Product Safety Commission (CPSC) and the Food and Drug Administration (FDA), created the National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance (NEISS-CADES) project by adding active surveillance of ADEs to the National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP). Because ADEs can be more difficult to identify than other injuries, an independent chart review in a sample of six NEISS-CADES hospitals was conducted to evaluate the sensitivity and predictive value positive (PVP) of ADE identification. This report describes the results of that evaluation, which indicated that although PVP for ADEs was high, the sensitivity was low, particularly for certain types of ADEs. As a result of these findings, additional training on identifying and reporting ADEs was initiated for all NEISS-CADES hospital coders. As more persons in the United States use drug therapies, active, postmarketing surveillance of ADEs can help identify safety problems and guide prevention efforts.