Misappropriating vulnerability: Assessing the utility of the social vulnerability index as a predictor of firearm violence.

The Social Vulnerability Index (SVI), a measure designed to gauge a community's resilience to natural disasters, such as hurricanes or wildfires, has been increasingly adopted in community violence research to identify places at risk of firearm-related harms. We take stock of recent research on social vulnerability and critically assess the conceptual and empirical validity of the SVI in the context of community firearm violence. We first compare the measurement properties of the SVI with a conventional index of concentrated disadvantage (CDI) commonplace in social science research on community violence. We then compare the empirical associations between firearm violence and the SVI and CDI in a series of tract-level, cross-sectional models in 84 American cities. Our results demonstrate that the SVI consistently underperforms relative to the traditional measure of CDI and that the SVI's explanatory power derives almost entirely from its socioeconomic status subtheme. Conceptually, the SVI measures a community's capacity to absorb exogenous shocks, not the structural determinants of violence. Methodologically, its rank-based equal-weighting scheme weakens construct validity. We argue that the reliance on SVI in the realm of firearm research represents a form of conceptual drift that risks misdirecting prevention resources and mischaracterizing the community-level origins of firearm harms in the United States.