b'DATA & INNOVATIONFigure 9. Trends in OHCA Outcomes and Interventions (2019-2024). The figure above illustrates trends in OHCA outcomes and interventions from 2019 to 2024 using a cohort-based approach applied to the CARES dataset. A noticeable decline across several key metrics occurred in 2020, coinciding with the onset of the COVID-19 pandemic. BCPR rates dropped slightly from 41.2% in 2019 to 40.5% in 2020, and public AED use fell sharply from 12.3% to 8.9%, reflecting public hesitancy to intervene due to concerns about virus transmission. Similarly, the incidence of shockable rhythm declined from 18.7% to 16.2%, and survival to hospital discharge decreased from 10.7% to 9.1%. Utstein survivala standardized measure among witnessed, shockable arrestsalso declined, from 34.7% to 31.1%. While gradual recovery is evident in subsequent years, with 2024 surpassing pre-pandemic levels in BCPR (42.0%) and public AED use (12.8%), survival metrics have only modestly improved. These trends underscore the pandemics lasting impact on emergency response systems and highlight the ongoing need for robust public education and bystander training to restore and improve OHCA outcomes.Despite the valuable insights provided by these analyses, national trend statistics remain a complex task due to the uneven participation of states in the CARES Quality Improvement Program and ongoing recruitment efforts. Some states have agencies that consistently report 100% of their OHCA cases year after year, which allows for a more reliable and comprehensive dataset for trend analysis. However, other states only have a handful of agencies contributing data, which limits the representativeness and accuracy of trend analysis at the national level. To ensure more accurate trend analysis, it is critical to include only the agencies that participate consistently from year to year. This approach will help eliminate biases introduced by states with fluctuating participation, leading to more reliable national trends. When all states are fully on board with 100% participation year after year, the resulting dataset will be more consistent, providing a clearer understanding of how trends are evolving across the country. The advancement to State NEMSIS v3.5 upload of CARES data will help improve compliance and enhance statewide data collection more efficiently and sustainably.60'