Grace Kim

Background Pediatric 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. Methods A 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. Results The 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. Conclusion This 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.

BACKGROUND: It is well established that young infants have the highest risk of severe pertussis, which often results in hospitalization. Since the 2012 recommendation of administering tetanus toxoid, diphtheria toxoid, and acellular pertussis (Tdap) vaccine for every pregnancy, evaluation of pertussis hospitalizations among young infants in the United States has been limited. METHODS: In this ecological study, we used the Kids’ Inpatient Database, the largest all-payer pediatric inpatient database in the United States, to study pertussis hospitalizations among infants <1 month of age from 2000 to 2016. RESULTS: The overall rate of pertussis hospitalizations before the Tdap vaccination recommendation was 5.06 per 100 000 infants (95% confidence interval, 4.36–5.76) and 2.15 per 100 000 infants (95% confidence interval, 1.49–2.81) afterward. CONCLUSIONS: This study supports maternal vaccination against pertussis as an important strategy in protecting young infants, and continued evaluation is needed to assess the long-term trends in hospitalization.