U.S. Department of Justice Office of Justice Programs Bureau of Justice Statistics Prevalence of Violent Crime among Households with Children, 1993-2010 Jennifer L. Truman, Ph.D., and Erica L. Smith, BJS Statisticians September 2012, NCJ 238799 ------------------------------------------ This file is text without graphics and many of the tables. A Zip archive of the tables in this report in Comma- delimited format (CSV) and the full report including tables and graphs in PDF format are available at: http://www.bjs.gov/index.cfm?ty=pbdetail&iid=4472 ------------------------------------------ In 2010, approximately 2.8 million children, representing 3.9% of all children age 17 or younger living in U.S. households, lived in a household in which at least one member age 12 or older experienced one or more nonfatal violent victimizations during the year (figure 1). This was a decline from 1993, when an estimated 8.7 million children, or 12.6% of all children age 17 or younger, lived in a household that experienced a violent victimization. The decline in the number of children living in a household in which at least one member experienced violent crime corresponds with the decline in overall violent victimization during the same period. The statistics in this report were developed from the Bureau of Justice Statistics’ (BJS) National Crime Victimization Survey (NCVS), which annually collects information on nonfatal victimizations against persons age 12 or older, reported and not reported to the police, from a nationally representative sample of U.S. households. This report focuses on children living in households in which at least one member age 12 or older was the victim of a nonfatal violent crime during a given year. As defined in the NCVS, nonfatal violent victimizations include rape, sexual assault, robbery, aggravated assault, and simple assault. The NCVS does not measure homicide. The NCVS defines a household as a group of members who all reside at a sampled address. These members may be family or nonrelatives, as well as children or adults. Households with children are classified into three distinct types— households with one or more children ages 0 to 11 only, households with one or more children ages 12 to 17 only, and households with at least one child age 0 to 11 and one child age 12 to 17. This report measures violent crime involving members of a household as victims, and reports on the annual prevalence of that violent crime among U.S. households with children from 1993 to 2010. The prevalence rate is the percentage of unique households in which at least one member age 12 or older experienced a violent victimization in a given year, regardless of the number or frequency of victimizations or the different types of victimizations those households experienced. The prevalence rate differs from the incident- based violent victimization rates commonly reported in statistics developed from the NCVS. (For more information, see Metholodogy.) This report describes the prevalence of violent victimization among the nation’s households and also presents estimates of the number of children living in a victimized household. These estimates were developed as an indicator of the extent to which children have direct and indirect exposure to violent victimization. The victimization of one household member is assumed to affect all other members of the household either emotionally, financially, or logistically. Data on nonfatal violent victimizations experienced by households were disaggregated by whether children lived in the household and by the location of the violent crime (i.e., inside the home or outside the home). These analyses, however, did not indicate if any children age 17 or younger living in victimized households were present during the violence, witnessed the violent crime, or were offenders involved in the violent crime. The data also did not provide information on the direct victimization of children ages 0 to 11. The prevalence measure, therefore, could not include households in which only children ages 0 to 11 were victims of violent crime and no other household members were victims of violent crime. For more information about the data, see Methodology. **************************************** ********** HIGHLIGHTS *********** * In 2010, an estimated 2.8 million children lived in a household in which at least one member age 12 or older experienced violent crime. This represents 3.9% of all children age 17 or younger living in U.S. households. * The number of children living in households that experienced violent crime was about 6 million fewer in 2010 than in 1993. * During 2010, about 1.6 million children ages 0 to 11 and 1.2 million children ages 12 to 17 lived in a household in which at least one member age 12 or older was the victim of violent crime during the year. * A smaller percentage of children ages 0 to 11 (3.4%) than children ages 12 to 17 (4.9%) lived in a household that experienced violent crime during 2010. * A greater percentage of children lived in households that experienced simple assault (2.6%), compared to serious violent crime (1.6%). * Among households with children in 2010, violent crime was most prevalent in households consisting of one adult with one child (6.5%) and households headed by a nonmarried adult (6.3%). * Violent crime was greatest among households with children that had an annual income of less then $15,000 (7.0%) and in urban areas (4.5%). *************************************** ------------------------------------------ Children in households with violent crime ------------------------------------------ About 6 million fewer children lived in a household that experienced violent crime in 2010, compared to 1993 The number of children age 17 or younger living in a household in which at least one member age 12 or older experienced one or more nonfatal violent victimizations in a given year declined by 68.2% from 8.7 million in 1993 to 2.8 million in 2010 (table 1). During this 18-year period, the decline among children ages 0 to 11 was 66.9%, and the decline among children ages 12 to 17 was 69.7%. Most of the decline occurred from 1993 to 2001. Over the 10-year period from 2001 to 2010, the number of children ages 0 to 11 living in a household in which a member age 12 or older was a victim of violent crime declined by 31.3% (from 2.3 million in 2001 to 1.6 million in 2010), while the number of children ages 12 to 17 living in a victimized household declined by 44.4% (from 2.1 million in 2001 to 1.2 million in 2010). ***************************************** In 2010, 3.9% of children in U.S. households lived in a household that experienced violent crime ***************************************** About 70.5 million children age 17 or younger lived in U.S. households in 2010 (table 2). An estimated 3.9% of these children (2.8 million) lived in a household in which at least one member age 12 or older was the victim of one or more nonfatal violent crimes. While a greater number of children ages 0 to 11 (1.6 million) than children ages 12 to 17 (1.2 million) lived in a victimized household in 2010, a smaller percentage of children ages 0 to 11 (3.4%) than children ages 12 to 17 (4.9%) lived in households that experienced violent crime. In 2010, more children lived in a household in which at least one member age 12 or older experienced the victimization outside the home (1.7 million or 2.4%), compared to inside the home (1.2 million or 1.7%). An estimated 0.2% of all children lived in a household that experienced violent crime both inside the home and outside the home (not shown in table). Comparable percentages of children ages 0 to 11 (1.6%) and ages 12 to 17 (1.8%) lived in households where a violent crime occurred inside the home. However, a greater percentage of children ages 12 to 17 (3.3%) than children ages 0 to 11 (2.0%) lived in households in which violent crime took place outside the home. These patterns remained true regardless of whether the victimization was a serious violent crime or simple assault. ******************************************* About 1.1 million children lived in a household that experienced serious violent crime in 2010 ******************************************* More children lived in households that experienced simple assault (1.8 million or 2.6%) than in households that experienced serious violent crime (1.1 million or 1.6%). This pattern held regardless of the children’s ages or whether the victimization was a serious violent crime or simple assault. An estimated 0.2% of all children lived in a household in which one or more members experienced both a serious violent crime and simple assault in 2010 (not shown in table). **************************************** The percentage of children living in a household that experienced violent crime declined by 68.9% from 1993 to 2010 **************************************** The percentage of children living in victimized households declined from 12.6% in 1993 to 3.9% in 2010 (figure 2). Over the 18-year study period, the percentage of children ages 12 to 17 who lived in households in which a member age 12 or older was the victim of one or more violent crimes declined from 17.8% to 4.9%. Among children ages 0 to 11, the percentage living in households experiencing violent crime declined from 10.2% to 3.4%. --------------------------------------- Households experiencing violent crime -------------------------------------- ****************************************** From 1993 to 2010, the percentage of households with children in which a member was a violent crime victim declined by 69.2% ****************************************** In 1993, children lived in 36.5 million U.S. households (not in figure). In 11.8% of these households, at least one member age 12 or older was the victim of one or more violent crimes (figure 3). By 2010, that percentage had declined to 3.6% of the 38.0 million U.S. households with children, representing a 69.2% decrease in the percentage of victimized households over the 18-year period. Households without children experienced a similar decline (64.1%) in the percentage that experienced violent crime, from 5.1% of the 63.3 million households in 1993 to 1.8% of the 84.9 million households in 2010. **************************************** Households with children were twice as likely as households without children to experience violent crime **************************************** In 2010, the overall percentage of households in which at least one member age 12 or older experienced one or more nonfatal violent victimizations was higher in households with children (3.6%) than households without children (1.8%). This pattern was also true for all previous years from 1993 to 2009. Each year from 1993 to 2010, the percentage of households with children in which at least one member age 12 or older was the victim of violent crime was about twice the percentage of households without children. *********************************** Among victimized households with children from 1993 to 2010, declines were similar across all children’s age groups *********************************** Among the three types of households with children—those with children 0 to 11 only, those with children ages 12 to 17 only, or those with children in both age groups—all experienced a decline in violent crime from 1993 to 2010. The magnitude of the decline from 1993 to 2001 was similar for all three household types. From 2001 to 2010, however, households with children ages 0 to 11 only experienced a smaller decline in violent crime than households with children ages 12 to 17 only. The percentage of households with children ages 0 to 11 only in which at least one household member age 12 or older experienced a nonfatal violent victimization declined from 7.8% in 1993 to 3.8% in 2001, and then to 2.9% in 2010 (table 3). The percentage of households with children ages 12 to 17 only that experienced violent crime also declined by about half (51.8%), from 16.3% in 1993 to 7.8% in 2001. Unlike households with children ages 0 to 11 only, the decline for households with children ages 12 to 17 continued at nearly the same pace (47.4%) through 2010, falling to 4.1%. Households with children in both age groups experienced a similar pattern of decline as households with children ages 12 to 17 only. The magnitude of decline in violent crime among households without children was statistically similar to the decline from 1993 to 2010 among households with children, as well as the shorter periods from 1993 to 2001, and from 2001 to 2010. *********************************** Violent crime was more prevalent in Households with children ages 12 to 17 (4.1%) than with children ages 0 to 11 (2.9%) *********************************** In 2010, violent crime was about twice as prevalent in households with children (3.6%) than households without children (1.8%) (table 4). Among the three types of households with children, both types of households in which children ages 12 to 17 lived experienced statistically similar rates of violent crime, regardless of whether the victimization was serious violent crime or simple assault. Moreover, households with children ages 12 to 17 only (4.1%) and households with children in both age groups (5.0%) experienced higher rates of violent crime than households with children ages 0 to 11 only (2.9%). The same pattern was also found in household prevalence rates for serious violent crime and simple assault. ************************************ About 4 in 10 victimized households with children experienced at least one violent crime inside the home in 2010 ************************************* Among the 1.4 million households with children in which at least one member age 12 or older was the victim of one or more violent crimes in 2010, a greater percentage of households had crime that occurred outside the home (62.4%) than inside the home (41.2%) (table 5). This pattern was similar among households with children ages 12 to 17 only and households with both children ages 0 to 11 and children ages 12 to 17. Among households with children ages 0 to 11 only, the percentage of households experiencing violent victimization inside the home and outside the home was similar. In the estimated 587,000 victimized households with children ages 0 to 11 only, nearly half had violent crimes that occurred inside the home (47.7%) and about half had crimes that occurred outside the home (56.6%). ************************************* Of households with children in which a member experienced serious violent crime in 2010, more than a third experienced the crime inside the home ************************************* Of the estimated 561,000 households with children in which at least one member age 12 or older experienced serious violent crime in 2010, 36.6% had a serious violent crime that took place inside the home. Similarly, of the 896,000 households with children in which a household member experienced simple assault, 43.8% of these households experienced the simple assault inside the home. Victimized households with children experienced serious violent crime inside the home and simple assault inside the home at similar percentages, with one exception. Among households with children ages 0 to 11 only, a smaller percentage experienced serious violent crime (35.7%) than simple assault (55.2%) inside the home. ************************************ Among households with children, violent crime was most prevalent in households with one adult and one child (6.5%) and households headed by a nonmarried adult (6.3%) ************************************ In general, the percentage of households in 2010 in which at least one household member was a victim of violent crime increased as the number of children in the household increased. About 3.4% of households with 1 or 2 children experienced violent crime (table 6). These households comprised about 80% of all households with children. In comparison, among the 1.8% of households with 5 or more children, the prevalence of violent crime was 6.8%. Households consisting of one adult and one child accounted for 8.4% of all U.S. households with children in 2010. The prevalence of violent crime among these households (6.5%) was higher than the prevalence of violent crime among households with children that had 3 or 4 persons (2.9%) or those with 5 or more persons (4.5%). Additionally, a third of all households with children were headed by nonmarried adults. Among these households, 6.3% had at least one household member age 12 or older who was a violent crime victim. In comparison, the remaining two-thirds of households with children were headed by married adults, but the prevalence of violent crime among these households was lower (2.3%). ************************************* Among households with children, violent crime was most prevalent in households with lower incomes and in urban areas ************************************** The prevalence of violent crime in households with children generally declined as household income increased. In 2010, about 7.9% of U.S. households with children had an annual income of less than $15,000 (table 7). Of these households, 7.0% had at least one member who was the victim of one or more violent crimes. In comparison, of the 24.3% of households with children in which a member had an annual income of $75,000 or more, an estimated 2.1% experienced violent victimization against a household member. In urban areas, households with children accounted for 30.8% of all households with children, and those in suburban areas accounted for an additional 53.5%. In urban areas, approximately 4.5% of the households with children had at least one household member who was the victim of violent crime in 2010. In comparison, a smaller percentage of households with children in suburban areas experienced violent crime (3.2%). Among households with children, 14.0% were headed by a black adult and 61.4% were headed by a white adult. The percentage of households with children in which at least one member was a victim of violent crime was larger among households headed by a black adult (4.9%), compared to those headed by a white adult (3.4%). ----------------- Methodology ----------------- **************** Survey coverage **************** The National Crime Victimization Survey (NCVS) is an annual data collection conducted by the U.S. Census Bureau for the Bureau of Justice Statistics (BJS). The NCVS is a self- report survey in which interviewed persons are asked about the number and characteristics of victimizations experienced during the prior six months. The NCVS collects information on nonfatal personal crimes (rape or sexual assault, robbery, aggravated and simple assault, and personal larceny) and household property crimes (burglary, motor vehicle theft, and other theft) both reported and not reported to police. In addition to providing annual level and change estimates on criminal victimization, the NCVS is the primary source of information on the nature of criminal victimization incidents. Survey respondents provide information about themselves (such as age, sex, race and ethnicity, marital status, education level, and income) and whether they experienced a victimization. Information are collected for each victimization incident about the offender (such as age, race and ethnicity, sex, and victim– offender relationship), characteristics of the crime (including time and place of occurrence, use of weapons, nature of injury, and economic consequences), whether the crime was reported to police, reasons why the crime was or was not reported, and experiences with the criminal justice system. The NCVS is administered to persons age 12 or older from a nationally representative sample of households in the United States. The NCVS defines a household as a group of members who all reside at a sampled address. Persons are considered household members when the sampled address is their usual place of residence at the time of the interview and when they have no usual place of residence elsewhere. Once selected, households remain in the sample for 3 years, and eligible persons in these households are interviewed every six months for a total of seven interviews. New households rotate into the sample on an ongoing basis to replace outgoing households that have been in sample for the 3-year period. The sample includes persons living in group quarters, such as dormitories, rooming houses, and religious group dwellings, and excludes persons living in military barracks and institutional settings, such as correctional or hospital facilities, and the homeless. (For more detail, see the Survey Methodology for Criminal Victimization in the United States, 2008, NCJ 231173, BJS website, May 2011.) In 2010, about 41,000 households and 73,300 individuals age 12 or older were interviewed for the NCVS. Each household was interviewed twice during the year. The response rate was 92.3% of households and 87.5% of eligible individuals. Victimizations that occurred outside of the U.S. were excluded from this report. From 1993 to 2010, 1,657 (0.8%) of the total 197,849 unweighted victimizations occurred outside of the U.S. ************************************* Weighting adjustments for estimating household victimization ************************************* Estimates in this report use data from the 1993 to 2010 NCVS data files. These files can be weighted to produce annual estimates of victimization for persons age 12 or older living in U.S. households. Because the NCVS relies on a sample rather than a census of the entire U.S. population, weights are designed to inflate sample point estimates to known population totals and to compensate for survey nonresponse and other aspects of the sample design. The NCVS data files include both person and household weights. Person weights provide an estimate of the population represented by each person in the sample. Household weights provide an estimate of the U.S. household population represented by each household in the sample. Both household and person weights, after proper adjustment, are also typically used to form the denominator in calculations of crime rates. Annual victimization estimates are derived by accumulating estimates across the two six-month interview periods. The weights of all crimes reported during interviews in that year are summed, regardless of when the crime occurred. This method provides annual estimates of victimization, the typical measure reported from NCVS analyses. This report, however, measures the prevalence of violent victimization among U.S. households. This prevalence estimate is a measure of the number of unique households in which at least one member age 12 or older experienced a violent victimization in a given year, regardless of the number or frequency of victimizations or the different types of victimizations those household members experienced. For example, if a household had three members, and one member was a victim of aggravated assault during the year, another member was a victim of robbery during the year, and the remaining member had no victimization during the year, the household would be counted only once in the prevalence rate as having been victimized by overall violent crime. The NCVS does not measure direct victimization of children ages 0 to 11. The prevalence estimates of nonfatal violent victimization experienced by household members living with children ages 0 to 11 is likely an underestimate, as there may be victims ages 0 to 11 living in households in which no other person age 12 or older reported a victimization. These households are not included in the numerator of the nonfatal violent crime household prevalence estimates. Household victimization weights were constructed to ensure that a household in which at least one member experienced one or more nonfatal violent victimizations in both six- month periods in a given year was counted only once in that annual prevalence estimate. If a household experienced a violent victimization in just one of the six-month periods, the household victimization weight was set equal to the sample household weight representative of the national household population at the time of the interview. If a household experienced a violent victimization in both six- month periods, the household victimization weight was set equal to half of this weight, so that these households would not represent twice the number of U.S. households in that year. From 1993 to 2010, households that experienced violent crime in both six-month periods in a given year represented about 0.2% of all households and 3.7% of all victimized households. See figure 4 for the trend in the prevalence of nonfatal violent crime among U.S. households for each six-month period from 1993 to 2010. Persons living at a sampled address may also change over the course of the three-year interview period, as one set of household members moves out and another set moves in. For these replacement households, it may not be appropriate to divide the weight in half, if there are different people in each six-month period. Analyses were conducted to investigate the impact of replacement household members on the annual household prevalence estimates. Of all the households in which at least one member age 12 or older experienced a nonfatal violent victimization from 1993 to 2010, an estimated 0.3% experienced violent crime in both six-month periods in a given year and were not the same set of household members in both sample periods. The household victimization weight was adjusted to account for this 0.3% of households, but the impact on the estimates was negligible. Given the imprecision of matching households across the sample period and the negligible impact on the household victimization estimates, the original construction of the household victimization weight was used. ***************************************** Weighting adjustments for estimating the number of children living in victimized households ***************************************** The NCVS collects data on the number of children ages 0 to 11 and ages 12 to 17 living in U.S. households. This report used these measures to develop weights to estimate the overall number of children living in households and the number of children living in households that experienced violent crime. The weight for the total number of children living in households--the denominator used to calculate the prevalence of children living in households that experienced violent crime—was calculated by taking the number of children in the household (age 17 or younger) and multiplying by the household weight for the year. For 2010, the NCVS estimate for the number of children age 17 or younger living in households, calculated using this weight, was about 70 million. That estimate is comparable to the 2010 U.S. Census Bureau estimate of about 74 million children. The weight for the number of children living in households that experienced violent crime—the numerator for the prevalence estimates—was calculated by taking the number of children in the household and multiplying by the household victimization weight previously described. Several data limitations are important to recognize. Estimates of both household victimization prevalence and the prevalence of children living in victimized households take into account only violent crime experienced by household members age 12 or older. Because the NCVS provides an overall count of children ages 0 to 11 in the household, however, households can be disaggregated based on the age of children in the households. Some victimization differences between households with younger children and households with older children may be attributed to the NCVS capturing only the direct victimization of children ages 12 to 17 and not children ages 0 to 11. **************************** Standard error computations **************************** When national estimates are derived from a sample, as is the case with the NCVS, caution must be taken when comparing one estimate to another estimate or when comparing estimates over time. Although one estimate may be larger than another, estimates based on a sample have some degree of sampling error. The sampling error of an estimate depends on several factors, including the amount of variation in the responses, the size of the sample, and the size of the subgroup for which the estimate is computed. When the sampling error around the estimates is taken into consideration, the estimates that appear different may, in fact, not be statistically different. One measure of the sampling error associated with an estimate is the standard error. The standard error can vary from one estimate to the next. In general, for a given metric, an estimate with a smaller standard error provides a more reliable approximation of the true value than an estimate with a larger standard error. Estimates with relatively large standard errors are associated with less precision and reliability and should be interpreted with caution. In order to generate standard errors around numbers and estimates from the NCVS, the Census Bureau produces generalized variance function (GVF) parameters for BJS. The GVFs take into account aspects of the NCVS complex sample design and represent the curve fitted to a selection of individual standard errors based on the Jackknife Repeated Replication technique. The GVF parameters were used to generate standard errors for each point estimate (such as counts, percentages, and rates) in the report. In this report, BJS conducted tests to determine whether differences in estimated numbers and percentages were statistically significant once sampling error was taken into account. Using statistical programs developed specifically for the NCVS, all comparisons in the text were tested for significance. The primary test procedure used was Student’s t-statistic, which tests the difference between two sample estimates. To ensure that the observed differences between estimates were larger than might be expected due to sampling variation, the significance level was set at the 95% confidence level. Data users can use the estimates and the standard errors of the estimates provided in this report to generate a confidence interval around the estimate as a measure of the margin of error. The following example illustrates how standard errors can be used to generate confidence intervals: According to the NCVS, in 2010, 3.9% of all children age 17 or younger lived in a household in which at least one member age 12 or older was the victim of one or more nonfatal violent crimes (see table 2). Using the GVFs, BJS determined that the estimate has a standard error of 0.2% (see appendix table 5). A confidence interval around the estimate was generated by multiplying the standard errors by ±1.96 (the t-score of a normal, two-tailed distribution that excludes 2.5% at either end of the distribution). Thus, the confidence interval around the 3.9% estimate from 2010 is equal to 3.9% ± .39% (0.2% X 1.96) or 3.51% to 4.29%. In others words, if different samples using the same procedures were taken from the U.S. population in 2010, 95% of the time the percentage of all children that lived in a victimized household would fall between 3.51% and 4.29%. In this report, BJS also calculated a coefficient of variation (CV) for all estimates, representing the ratio of the standard error to the estimate. CVs provide a measure of reliability and a means to compare the precision of estimates across measures with differing levels or metrics. In cases where the CV was greater than 50%, or the unweighted sample had 10 or fewer cases, the estimate was noted with a “!” symbol (interpret data with caution; estimate based on 10 or fewer sample cases, or the coefficient of variation exceeds 50%). *************************** Methodological changes to the NCVS in 2006 **************************** Methodological changes implemented in 2006 may have affected the crime estimates for that year to such an extent that they are not comparable to estimates from other years. Evaluation of 2007 and later data from the NCVS conducted by BJS and the Census Bureau found a high degree of confidence that estimates for 2007, 2008, 2009, and 2010 are consistent with and comparable to estimates for 2005 and previous years. The reports, Criminal Victimization, 2006, NCJ 219413, December 2007; Criminal Victimization, 2007, NCJ 224390, December 2008; Criminal Victimization, 2008, NCJ 227777, September 2009; Criminal Victimization, 2009, NCJ 231327, October 2010; and Criminal Victimization, 2010, NCJ 235508, September 2011, are available on the BJS website. ****************************************** The Bureau of Justice Statistics is the statistical agency of the U.S. Department of Justice. James P. Lynch is the director. This report was written by Jennifer L. Truman, Ph.D., and Erica L. Smith. Shannan Catalano verified the report. Morgan Young and Jill Thomas edited the report, and Jayne E. Robinson and Morgan Young produced the report, under the supervision of Doris J. James. September 2012, NCJ 238799 ****************************************** ****************************************** Office of Justice Programs Innovation • Partnerships • Safer Neighborhoods www.ojp.usdoj.gov ****************************************** ******************** 9.5.2012/JER/ 10:00am ********************