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

caregiver were 1.3 times more likely to experience endangerment compared with childrenwith a grandparent caregiver.5.5 Family Size Differences in the Incidence of MaltreatmentAnalyses examining the relationship between family size 84 and the incidenceof child abuse and neglect categorized children into one of four groups on the basis of thenumber of children in their family: those in families where they were the only child, thosein families with two children, three children, and four or more children. 85,865.5.1 Family Size Differences in Harm Standard MaltreatmentThe incidence of a few categories of Harm Standard maltreatment variedacross the family-size groups. Figure 5–17 graphs these categories, showing that theyhave a consistent pattern: incidence rates are higher for children in the largest families,intermediate for “only” children, and lowest for children in families with two or threechildren.Harm Standard Maltreatment CategoriesOverall Harm Standard maltreatment. An estimated 21.2 children inhouseholds with four or more children suffered some form of Harm Standardmaltreatment, which is equivalent to 2.1 children per 100, or 1 in 48 children in theselarger families. This, the highest rate, is 1.8 times the lowest rate (11.9 per 1,000 children84 As in previous NIS reports, “family size” reflects the number of children in the household rather than thenumber of children within separate family units in a household.85 Computations of incidence rates used the following population denominators, reflecting the number (inthousands) of children in the general population: 16,791 children in one-child households, 28,919 childrenin two-child households, 17,413 children in three-child households, 10,511 children in four-childhouseholds (U.S. Census Bureau, 2008a, 2008b, 2008c).86In each category of maltreatment or level of harm, decisions about the significance of differences reliedon the Bonferroni critical values for t. This adjusted for the multiplicity of the comparisons involved.Appendix D gives the details concerning the statistical tests for significance of family size differences.5–43