The NIS is a congressionally mandated, periodic research effort to assess the incidence of child abuse and neglect in the United States. The NIS has been conducted approximately once each decade, beginning in 1974, in response to requirements of the Child Abuse Prevention and Treatment Act. Although the Children’s Bureau collects annual state-level administrative data on official reports of child maltreatment, the NIS studies are designed to estimate more broadly the incidence of child maltreatment in the United States by including both cases that are reported to the authorities as well as those that are not. A unique contribution of the NIS has been the use of a common definitional framework for classifying children according to types of maltreatment as well as the severity of maltreatment.

The NIS gathers information from multiple sources to estimate the number of children who are abused or neglected, providing information about the nature and severity of the maltreatment, the characteristics of the children, perpetrators, and families, and the extent of changes in the incidence or distribution of child maltreatment since the time of the last national incidence study. The NIS design assumes that the maltreated children who are investigated by child protective services (CPS) represent only the “tip of the iceberg.” Although the NIS estimates include children investigated by CPS, they also include maltreated children who are identified by professionals in a wide range of agencies in representative communities. The NIS-4, the most current data collection, gathered data in a nationally representative sample of 122 counties selected to ensure the necessary mix of geographic regions and of urban and rural areas. Information related to NIS-1, NIS-2 and NIS-3 can be found at https://www.childwelfare.gov/topics/systemwide/statistics/nis/.