This number had to be estimated through the use of variables from both the March and April surveys. Four questions from the April CSS were used:
- PES400: If the respondent reported ever having contacted a child support enforcement or IV-D office, a department of social services, a welfare office, or any state or local government agency about anything to do with child support, than he/she was included.
- PES401: If the respondent reported ever having been contacted by one of these agencies about anything to do with child support, then he/she was included.
- PES300: Individuals were asked if the non-custodial parent was supposed to make any payments for their child between January 1 and December 31, 2001. If the respondent answered that they didn't know because the Child Support Enforcement Office had filed the paperwork, then he/she was included.
- PES303: Individuals were asked how payments were supposed to be sent to them. If the respondent replied that payments were to be sent by a child support, welfare, or other public agency, then he/she was included.
In addition, all families in which income was received from TANF or in which either the parent or child was covered by Medicaid were included in the estimation of the IV-D caseload. These families were designated by the March CPS variables FINC_PAW (family income received from public assistance or other welfare) and MCAID (the parent or child was covered by Medicaid). This assumption was made because of the child support enforcement cooperation requirements that are part of the regulations guiding those programs.