Social Vulnerability Index

The Centers for Disease Control and Prevention (CDC) developed a Social Vulnerability Index (SVI) using 16 census variables. Social Vulnerability is the extent to which an area's social conditions affect the response and prevention of disasters. The SVI was created to help differentiate the relative vulnerability of a particular place from those around it.

The 16 census tract variables are sorted by commonality into four different themes: Socioeconomic Status, Household Characteristics, Racial and Ethnic Minority Status, Housing Type and Transportation. These four themes comprise the SVI.

Image: CDC (https://www.atsdr.cdc.gov/placeandhealth/svi/documentation/SVI_documentation_2020.html)

Rationale

Lowest Granularity

Calculation

Interpretation

The county-level SVI Percentile compares the counties within Delaware to all other counties within the United States. The interpretation of the county level percentiles is that N county with an SVI of X means that X % of counties in the United States are less vulnerable than N county and (1-X)% of counties in the US are more vulnerable than N county (where N is the county selected for interpretation and X is the SVI Percentile of the chosen county).

The census tract level SVI Percentile compares the census tracts within Delaware to all other census tracts within Delaware. The interpretation of the census tract level percentile is that Census Tract N with an SVI of X means that X % of census tracts in Delaware are less vulnerable than Census Tract N and (1-X)% of Census Tracts in Delaware are more vulnerable than N census tract (where N is the census tract selected for interpretation and X is the SVI Percentile of the chosen census tract).

This interpretation can apply the understanding for the county and census tract level data to the Overall Rating Percentile and the Percentile for each of the four themes that make up the Overall SVI Percentile.