Fourth National Incidence Study of Child Abuse and Neglect (NIS–4)

Supplementary studies. In addition to the main study, the NIS–4 projectincluded three supplementary studies, designed to enhance the interpretability of the NISfindings. Two were surveys of CPS agencies—one on their overall structure andpractices and the second on their screening standards for deciding whether to investigatea referral of suspected maltreatment. The third supplementary study was a survey ofsentinels on their backgrounds and definitions of child abuse and neglect and concerningtheir standards for reporting suspected maltreatment to CPS or submitting data onmaltreated children to the NIS. A fourth study is also planned, which will compare theNIS information on CPS cases with parallel data collected by the NCANDS to crossvalidatethese sources and identify any notable differences in the information theyprovide.2.2Samples and RecruitmentThe NIS target population is the set of children under 18 years of age who aremaltreated during the study period, including all who are investigated by child protectiveservices (CPS) agencies and others who come to the attention of communityprofessionals working in specific categories of agencies.Samples. The NIS–4 first-stage sample comprised 122 counties. Themethod used to sample these counties ensured that they represented different regions ofthe country, degrees of urbanization, crime rates, percentage of households headed bysingle women, and CPS substantiation rates. The second stage of the sample consisted ofagencies in the selected counties. Sampled agencies included all the 126 local CPSagencies that served the 122 NIS–4 counties, as well as 1,524 sentinel agencies in thecounties. The sentinel agencies represented all county sheriff departments, countydepartments of juvenile probation, public health, and public housing, and samples ofmunicipal police departments, hospitals, shelters, day care centers, schools, other socialservices and mental health agencies. The third stage of the sample entailed samplinginvestigated cases in CPS agencies to gather details about the children, families, andmaltreatment and, in the sentinel agencies, selecting the staff to serve as sentinels andwatch for children maltreated during the study period. The listing of CPS caseinvestigations during the reference period totaled 140,206, and the NIS–4 sampled 11,930for the detailed maltreatment data. The NIS–4 identified 22,117 eligible staff inparticipating sentinel agencies and sampled 11,321 to be recruited as sentinels.2–7