State & Local Programs

Calculating Disproportionality

From the the National Council of Juvenile and Family Court Judges' Technical Assistance Bulletin - Disproportionality Rates of Children of Color in Foster Care, May 2011

Disproportionality is defined as the level at which groups of children are present in the child welfare system at higher or lower percentages or rates than in the general population. Robert Hill (2006) developed the “disproportionality index” as an indicator of the degree a given jurisdiction is disproportionate.The disproportionately index is calculated by taking the proportion of children in foster care for a given race and dividing it by the proportion of the same racial group in the child population. This creates a ratio where scores ranging from 0.00 to 0.99 are indicative of underrepresentation, scores of 1.0 indicate no disproportionality, and scores of 1.1 and greater indicate overrepresentation. For example, in a community where 40% of the children entering foster care are African American, and only 20% of the child population is African American, the disproportionality index would be 2.0, indicating African Americans are twice as represented in foster care as they are in the general population. Disproportionality scores are calculated for the number of children “entering” care, “exiting” care, and “remaining” in care at the end of the year. These calculations require (1) thechild population(by race) for any given state or jurisdiction, available from census data; and (2) thenumber of children in the child welfare system (by race),available from the AFCARS.

Data Sources:

  • Data Element Available From Most Recent Date Child Population (by Race)
    The U.S. Census Bureau
    (Total Population – Adult Population)
  • Number of Children In Care, Entering Care, Exiting Care (by Race)
    National Data Archive on Child Abuse and Neglect’s Adoption and Foster Care Analysis and Reporting System (AFCARS)




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