Social Vulnerability Index (SVI)

What are social vulnerabilities?

Social vulnerability refers to resilience, which is the ability to “bounce back.”  Social vulnerability is a measure of how well communities may respond when confronted by external stresses on human health, natural or human-caused disasters or disease outbreaks.  Reducing social vulnerability can decrease both human suffering and economic loss.

What  is socioeconomic status?

Socioeconomic status is a combination of sociological and economic statistics.  It is often measured as a combination of education, income and occupation.  Some people think of socioeconomic status as someone's social standing of a person or community.  From the Public Health viewpoint, there are connections between socioeconomic status and health outcomes.  Lower socioeconomic status may put people at higher risk for poor nutrition, lower education, inadequate housing, higher crime, higher risk behaviors and less access to health care.

What is the Social Vulnerability Index (SVI)?

The federal Agency for Toxic Substances and Disease Registry (ATSDR) uses U.S. Census data to calculate the Social Vulnerability Index (SVI).  The ATSDR’s Geospatial Research, Analysis & Services Program (GRASP) created SVI as a tool to help public health officials and emergency response planners.  SVI can help to identify communities that may need the most support before, during, and after a hazardous event.

The SVI indicates the relative vulnerability of every U.S. Census tract. Census tracts are subdivisions of counties for which the U.S. Census collects statistical data.  The SVI tool ranks the tracts on 14 social factors such as unemployment, lack of vehicle access, and crowded housing.  The SVI tool groups social factors into four related themes.  Each tract receives a separate ranking for each of the four themes, as well as an overall ranking.  The four themes in the SVI tool are:

  • Socioeconomic status - income, poverty, employment and education
  • Household composition - age, single parenting and disability
  • Minority status and language - race, ethnicity
  • English Language Proficiency, housing and transportation - housing structure, crowding and vehicle access