Notes on Source Data

The main sources of data for this site are the University of California, Berkeley quarterly extracts from the California Department of Social Services (CDSS) Child Welfare Services/Case Management System (CWS/CMS). These extracts are pulled approximately one month after each quarter ends, and the data are fully refreshed each quarter. Due to the time it takes to process, run, and validate the data, information on the website and in the California CWS Outcomes System reports is between three and six months old.

Refresh Schedule

Extract name Data cutoff Website refreshed by
Quarter 1 April 1 July 1
Quarter 2 July 1 October 1
Quarter 3 October 1 January 1 (following year)
Quarter 4 January 1 April 1
For example, the CWS/CMS 2020 Quarter 3 Extract (Q3 20) reported on events up to the data cutoff of October 1, 2020. Reports based on the Q3 20 extract were available on the website by January 1, 2021.

For reporting purposes, we use the CWS/CMS extracts to construct three primary longitudinal analysis files types (allegation, foster care, and case) which track children’s histories in the Child Welfare System. In addition to specifying supervising county and capturing child-level demographics, these files include additional information:

Allegation File - This file includes one row for each allegation for each child, including allegation type, reporter type, responses such as investigation, as well as allegation disposition (e.g., substantiated, inconclusive, and unfounded).

Foster Care Files - These files include one row for each placement home for each child, including dates of entries and exits to foster care, placement type, and length of stay.

For the general foster care reports (entries, in care, and exits), children in non-dependent guardian placements are included.
To replicate the methodology used in the six federal Child and Family Service Reviews (CFSR3) performance measures concerned with children in care (Measure 3-S2 is concerned exclusively with allegations), a slightly different source file, which mirrors the Adoption and Foster Care Analysis and Reporting System (AFCARS) file, is used. This file excludes children in non-dependent guardian placements. However, this file differs from the federal AFCARS file in two ways: (1) episodes that transition from child welfare to probation or probation to child welfare on the same day are bridged into a single episode, and (2) all probation foster care placements are included, not just those receiving federal funds. The federal and state views of the CFSR3 measures contain only children under the age of 18.
In both files, consistent with AFCARS reporting, episodes of zero or one day are excluded. If the case that is open during a placement episode has the Intervention Reason Type "Incoming ICPC Request" (Code 1226) [ICPC = Interstate Compact on the Placement of Children], then that placement is excluded, since it is reported by the state sending the child to California.

Case Files - The primary file includes one row for each case service component for each child. Secondary files serve to locate cases within caseloads, offices, and counties. The files include information about children’s case services, including case openings and closings, and service components.

Population Data File - Child population counts by county with demographic breakouts including age, race/ethnicity and sex at birth.

The child population and rates reports use the California Department of Finance (DOF) annual population estimates and projections.