Addressing population health and health inequalities: The role of fundamental causes

Objectives. As a case study of the impact of universal versus targeted interventions on population health and health inequalities, we used simulations to examine (1) whether universal or targeted manipulations of collective efficacy better reduced population-level rates and racial/ethnic inequalities in violent victimization; and (2) whether experiments reduced disparities without addressing fundamental causes. Methods. We applied agent-based simulation techniques to the specific example of an intervention on neighborhood collective efficacy to reduce populationlevel rates and racial/ethnic inequalities in violent victimization. The agent population consisted of 4000 individuals aged 18 years and older with sociodemographic characteristics assigned to match distributions of the adult population in New York City according to the 2000 US Census. Results. Universal experiments reduced rates of victimization more than targeted experiments. However, neither experiment reduced inequalities. To reduce inequalities, it was necessary to eliminate racial/ethnic residential segregation. Conclusions. These simulations support the use of universal intervention but suggest that it is not possible to address inequalities in health without first addressing fundamental causes.