US Pediatric Drowning Trends: A System Dynamics Scoping Model Based on Global Burden of Disease (GBD) Estimates

BackgroundPediatric drowning remains a leading cause of unintentional injury death globally. Current prevention research primarily focuses on single interventions, often failing to account for the complex interactions and feedback mechanisms that drive population trends. This study demonstrates the utility of system dynamics (SD) modeling as a scoping tool to construct and test causal feedback hypotheses. MethodsA scoping model was developed to simulate the drivers of pediatric drowning epidemiology. Modeling was based on historical drowning morbidity and mortality estimates of one US state from the Global Burden of Disease (GBD) initiative (1990 to 2021), supplemented by secondary literature. Key feedback loops--including the hypothesized intergenerational transfer of swimming competency and the impact of perceived risk on water supervision and prevention investments--were explicitly mapped within the model structure. ResultsThe model successfully replicated the non-constant decline in pediatric drowning deaths observed in the state-specific GBD data: 50.6 per 100,000 in 1990 versus 25.7 per 100,000 in 2021. Analyses identified the balancing feedback loop (B1) of "Reduced Risk Perception" as a dominant structure. This causal mechanism illustrates that sustained success in mortality reduction can inadvertently lower Perceived Prevalence, subsequently reducing Public Concern and prevention investments, thereby slowing the overall rate of decline. ConclusionThis study demonstrates that SD modeling is a powerful and accessible tool for testing aggregate, long-term hypotheses regarding unintentional drowning trends. It provides a framework for designing integrated, dynamic prevention strategies that account for the system tendency to adapt and introduce counter-intuitive outcomes. WHAT IS ALREADY KNOWN ON THIS TOPICPediatric drowning rates have decreased due to several hypothesized measures, including improved pool fencing, increased parental supervision, and expanded access to swimming lessons. However, the main scientific knowledge gap is a lack of understanding regarding how these individual interventions interact over time within a complex social system. Specifically, it remains unclear how success in one area (e.g., mortality reduction) influences the effectiveness or sustainability of other measures (e.g., public vigilance and funding). WHAT THIS STUDY ADDSBy integrating Global Burden of Disease (GBD) estimates into a system dynamics framework, this study identifies the causal structures driving observed mortality trends. We identify a "success-bred complacency" dominant causal mechanism that explains the non-linear plateaus and reversals often seen in long-term injury data. HOW MIGHT THIS STUDY AFFECT RESEARCH, PRACTICE, OR POLICYSystem dynamics modeling allows for studying shifts in dominant causal feedback mechanisms over time. Future work to disaggregate model trends by pediatric group characteristics (e.g., race and ethnicity) is necessary to inform strategies that further prevent pediatric unintentional drowning.