Child maltreatment can be defined as “behavior towards [a child] . . . which (a) is outside the norms of conduct, and (b) entails a substantial risk of causing physical or emotional harm. Behaviors included will consist of actions and omissions, ones that are intentional and ones that are unintentional.” Four types of maltreatment are generally recognized, including physical abuse, sexual abuse, neglect (including educational neglect, medical neglect, and other forms), and emotional maltreatment. Before 2009, all data in this report represent all substantiated or indicated cases from reporting states in a given year. For 2009 and subsequent years, duplicate victims (that is, those reported to have experienced more than one incidence of maltreatment) are excluded, and data represent the number of children who had at least one substantiated or indicated case in that year. Not all states report duplicate victims, so the total number of unique victims is an estimate based on available numbers. Legal definitions of maltreatment vary by state.
Child Trends. (2019). Child maltreatment. Retrieved from https://www.childtrends.org/indicators/child-maltreatment.
 States use different terminology to refer to the status of maltreatment reports that have, upon investigation, yielded evidence that abuse or neglect has occurred.
 U.S. Department of Health and Human Services, Administration for Children and Families, Children’s Bureau. (2012). Child maltreatment 2011. Washington, DC: Author. Retrieved from http://www.acf.hhs.gov/programs/cb/resource/child-maltreatment-2011.
 Finkelhor, D., Saito, K., & Jones, L. M. (2016). Updated trends in child treatment. Durham, NH: University of New Hampshire, Crimes Against Children Research Center. Retrieved from http://www.unh.edu/ccrc/pdf/Updated%20trends%202014.pdf.
 Christoffel, K. K., Scheidt, P. C., Agran, P. F., Kraus, J. F., McLoughlin, E., & Paulson, J. A. (1992). Standard definitions for childhood injury research: Excerpts of a conference report. Pediatrics, 89(6), 1027-1034.