573547

research-article2015

IJOXXX10.1177/0306624X15573547International Journal of Offender Therapy and Comparative CriminologyTurner et al.

Article

On the Association Between Repeat Bully Victimizations and Carrying a Firearm: Evidence in a National Sample

International Journal of Offender Therapy and Comparative Criminology 1­–26 © The Author(s) 2015 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0306624X15573547 ijo.sagepub.com

Michael G. Turner1, Matthew D. Phillips1, Henry B. Tigri1, Meredith A. Williams2, and Jennifer L. Hartman1

Abstract Bullying is a significant public concern. The purpose of the present study is to investigate whether being repeatedly victimized by a bully during childhood and adolescence is associated with gun carrying in adolescence and adulthood. Using data from the National Longitudinal Survey of Youth 1997, we found that just over one fourth of the respondents reported carrying a gun at some point in their lifetime. Respondents experiencing repeat bully victimizations reported higher rates of gun carrying during the last 12 months and the last 30 days. No support was found for the association of repeat bully victimizations and carrying a gun to school. Individuals victimized during childhood (before the age of 12) and during adolescence were found to be at risk of carrying a gun later in the life course. Repeat bully victimizations should be considered a marker for gun-carrying behaviors in adolescence and adulthood. Keywords bully victimization, bullying, firearm Although rates of violent offending have decreased in recent decades, gun violence remains a significant problem in our society (Braga, 2012). According to the Federal Bureau of Investigation’s Uniform Crime Reports (UCR), 274,153 crimes were 1University 2University

of North Carolina–Charlotte, USA of Cincinnati, OH, USA

Corresponding Author: Michael G. Turner, Department of Criminal Justice and Criminology, University of North Carolina– Charlotte, 5070 Colvard Hall, 9201 University City Blvd., Charlotte, NC 28223-0001, USA. Email: [email protected]

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committed by an assailant using a firearm in the year 2010 alone (U.S. Department of Justice, Federal Bureau of Investigation, 2011). In that same year, the National Crime Victimization Survey (NCVS) indicates that firearms were used in 337,960 violent crimes (not including murders; Truman, 2011). In light of recent tragedies involving mass shootings, including the Sandy Hook Elementary School and the Aurora, Colorado, movie theater incidents, violent offending occurring with firearms continues to capture national attention. In fact, these recent events have stimulated political debate focused on the impact of enacting more restrictive gun control policies (Steinhauer, 2013). At the same time, the National Rifle Association (NRA) has proactively suggested that schools hire armed police officers to prevent mass shootings from occurring on school grounds (Lichtblau & Rich, 2012). Taken together, these empirical facts and current events have fostered a resounding scientific and public interest in understanding the antecedents associated with carrying a gun. One potential antecedent that has received some empirical attention is whether individuals experience repeated bully victimizations (Glew, Fan, Katon, Rivara, & Kernic, 2005; Nansel, Overpeck, Haynie, Ruan, & Scheidt, 2003). Briefly defined, bullying has been identified as the continual harassment (physical, verbal, emotional, or psychological) of one individual by another where there exists a power imbalance (Nansel et al., 2001). Research investigating the relationship between bullying and carrying a gun has consistently found that compared with those not involved in bullying incidents, bullies and bully-victims—individuals involved in both bullying as well as being victimized by bullies—experience elevated probabilities of carrying a gun (Andershed, Kerr, & Stattin, 2001; Glew, Fan, Katon, & Rivara, 2008; Stein, Dukes, & Warren, 2007). Research focused solely on bully victimization and gun carrying, however, has been equivocal. For example, using a subsample of youths between the ages of 12 and 14, Haddow (2006) found no significant difference in carrying a gun to school between non-victims and individuals victimized by a bully before the age of 12 (see Table 1). Likewise, using seven waves of the National Longitudinal Survey of Youth 1997 (NLSY97), Wong and Schonlau (2013) failed to attain a treatment effect of repeated bully victimization on the probability of carrying a handgun. In contrast, using a national sample of 15,686 students in Grades 6 through 10, Nansel and her colleagues (2003) found that victims of bullies, particularly frequent victims, were at an elevated probability of carrying a gun; individuals who were only occasionally victimized were not significantly affected. Combined, these findings appear to suggest that whereas more limited involvement in bully victimizations is not associated with carrying a firearm, more frequent bully victimizations do result in higher probabilities of gun carrying. The extant research has also documented a relationship between being victimized by a bully and individual’s perceptions about carrying a firearm. Glew and her colleagues (2005) found that among a sample of 3,530 students in Grades 3 through 5, bullies were the most likely to support carrying guns to school. In subsequent research, Glew and her colleagues found that only bully-victims were significantly more likely to support carrying a gun to school. Bullies and individuals who were only victimized by a bully did not support these attitudes.

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Table 1.  Literature Investigating the Relationship Between Bully Victimizations and Carrying a Firearm. Study Simon, Dent, and Sussman (1997)

Sample 504 high school students from Southern California

Measure of bully victimization Likelihood of victimization in the year to come

Measure of firearm/ gun Whether or not carried knife or gun to school in the last year

Findings Perception of vulnerability to victimization positively associated with weapon carrying at both bivariate and multivariate levels Higher frequency of bullying others strongly associated with higher risk. Bullies highly likely to be “high-risk” gun owners. Nothing said about victims. Low-risk (for sport) gun owners have low rates of anti-social behavior

Surveyed about accessibility and reason for use/ownership. Combined these with anti-social behavior to label as “high-risk” or “low-risk” Strong association between Have you carried Whether or not Wilcox and Clayton 6,169 students carrying a firearm and weapon (not only threatened, had (2001) in 6th to 12th parents owning guns. Fear gun) to school in property stolen, or grades in insignificant, but threats last 30 days? afraid of someone Kentucky and theft significantly at school in last increased carrying a firearm. 30 days Controlling for school structure, all hold true except parental ownership. 12-14 group more likely to Have you carried Before age 12, were Luster and Oh 2,813 males aged carry if bullied in bivariate handgun in last 12 you victim of (2001) 12 to 14 and model. Insignificant in months? repeated bullying? 1,806 males aged multivariate. Bullying not 15 to 16 from predictive of older group NLSY at all Male and female bullies and Andershed, Kerr, 2,561 8th graders How often bullied in Number of times bully-victims strongly and Stattin (2001) in Sweden last 2 months? carried “weapon” associated with carrying out on streets at weapon at night on streets. night Males more than females. Bully-victims significantly more than bullies Aggressive attitude nonDid you carry a Victimized in last 8,273 students in Brockenbrough, victims reported highest gun to school month. Needed 7th, 9th, and Cornell, and levels of gun carrying (no time frame at least 3 actions 11th grades in Loper (2002) followed by aggressive given)? (i.e., punched, suburban Virginia attitude victims and nonshoved, threatened) aggressive attitude victims and more than 1 and non-victims (both equal) occurrence in the last month to be considered victim Frequency they have Number of days (in Being bullied corresponded Nansel, Overpeck, 15,686 students with carrying a weapon last 30 days) they been bullied in in 6th to 10th Haynie, Ruan, and for both males and females carried gun, knife, school and away grades in public Scheidt (2003) while adjusting for other or club from school since and private factors. The results are the current term schools stronger for those who get bullied more frequently. No controls for weapon carrying at Time 1 Cunningham, Henggeler, Limber, Melton, and Nation (2000)

6,263 students in 5th through 7th grades (aging 9-16) from nonmetropolitan schools in Southeast

Frequency of bullying behavior in last 3 months

(continued)

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Table 1.  (continued) Study Glew, Fan, Katon, Rivara, and Kernic (2005)

Haddow and Haddow (2006) Stein, Dukes, and Warren (2007)

Sample

Measure of bully victimization

Frequency of “made 3,530 students in fun of, bothered, 3rd, 4th, and 5th hurt” (no time grades in urban frame given) public schools on West coast Before age 12, were 4,807 aged 12 to you a victim of 14 years from repeated bullying? NLSY Frequency in past 12 1,312 male months hit, kicked, students in 7th shoved, threatened to 12th grades in by someone Colorado stronger

Glew, Fan, Katon, 5,391 students in and Rivara (2008) Grades 7, 9, and 11 in an urban public school district

How often one is bullied or bullies others?

Measure of firearm/ gun

Findings

Bullies and non-responders How wrong do were more likely than you think it is to bystanders to endorse take a handgun to carrying guns to school school? If you have access, No significant difference in carrying between victims have you carried and non-victims gun to school? Bully-victims reported much Number of more weapon possession times (in last than the bullies, the neutrals, 12 months) and the victims possessed gun, club, knife at school, schoolsponsored event, while out with friends How wrong do you Only bully-victims significantly more likely to endorse think it is to carry carrying gun to school a gun to school?

Note. NLSY = National Longitudinal Survey of Youth.

The purpose of the present study is to use a national sample of longitudinal data to investigate the potential effects that experiencing repeat bully victimizations during childhood and adolescence possess on carrying a firearm in adulthood. To investigate whether the timing of the victimization as well as the dosage of the victimization had unique effects on gun carrying, we further disaggregate the victimization measure into (a) childhood victims, (b) adolescent victims, and (c) chronic victims (those victimized during childhood and adolescence). We begin with a review of the literature.

The Effects of Bully Victimization The pursuit of scientific knowledge focusing on understanding whether bullies or victims of bullies experience adverse effects later in the life course has occurred for the past two decades. A review of the bullying and bully victimization research reveals two important themes. First, bully-victims—those who bully as well as have been victimized by a bully—typically report higher levels of adverse outcomes later in the life course (Forero, McLellan, Rissel, & Bauman, 1999; Juvonen, Graham, & Schuster, 2003; Nansel, Craig, Overpeck, Saluja, & Ruan, 2004; Nansel et al., 2001; Veenstra et al., 2005; Wolke, Woods, Bloomfield, & Karstadt, 2000). This finding suggests that the co-participation in both offending and victimization (in terms of bullying) has more impactful long-term consequences than involvement in either one independently. Second, individuals who bully most frequently, or were bullied most frequently,

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generally report the highest levels of adverse consequences (Klomek et al., 2009; Nansel et al., 2003; Sourander, Jensen, Ronning, Elonheimo, et al., 2007; Sourander, Jensen, Ronning, Niemela, et al., 2007). The dose-effect of offending and victimization on adverse consequences has also emerged in delinquency and crime more generally (see Piquero, Farrington, & Blumstein, 2003). Empirical evidence related to the impact of bullying indicates that those who bully and/or experience a bully victimization report disproportionately higher levels of adverse social, psychological, legal, and mental health outcomes (Klomek, Marrocco, Kleinman, Schonfeld, & Gould, 2007; Kumpulainen & Rasanen, 2000; Nansel et al., 2003; Sharp, Thompson, & Arora, 2000; Sourander, Helstela, Helenius, & Piha, 2000; Turner, Exum, Brame, & Holt, 2013; van der Wal, de Wit, & Hirasing, 2003; Wong & Schonlau, 2013). Interestingly, research has also linked bully victimization experiences with adverse outcomes related to substance abuse (Sullivan, Farrell, & Kliewer, 2006), eating disorders (Kaltiala-Heino, Rissanen, Marttunen, Rimpela, & Rantanen, 1999), injury (Laflamme, Engström, Möller, Alldahl, & Hallqvist, 2002), and general health problems (Boey & Goh, 2001). Although empirical evidence has prospectively explored the link between experiencing bully victimizations and carrying a firearm, a growing number of highly publicized school shootings have retrospectively linked offenders’ histories to experiencing bully victimizations. Anecdotal reports of the shooters in the Columbine experience in 1999 suggested that prior to their attack, other students repeatedly targeted them in bullying incidents (Limber, 2002). A government investigation of 37 school shootings found that 65% of school shooters reported experiencing moderate to severe bullying by their peers while in school (Vossekuil, Reddy, Fein, Borum, & Modzeleski, 2000). A more sophisticated empirical analysis of school shootings occurring over a 5-year period from 1994 to 1999 found that school shooters were twice as likely as their victims to experience severe bully victimizations (Anderson et al., 2001). Combined, these descriptive studies begin to paint the picture that bully-victims take measures to retaliate with deadly force against their offenders and this often involves the use of a firearm. Notwithstanding these results, the relationship between being victimized—in general, and specifically by a bully—and carrying a firearm remains complex. Several studies have found significant positive associations between gun ownership and criminal victimization (Lizotte & Bordua, 1980; Marciniak & Loftin, 1991; Whitehead & Langworthy, 1989). These findings have been balanced by research that has failed to produce findings in support of a positive association between gun ownership and criminal victimization (Cao, Cullen, & Link, 1997; DeFronzo, 1979; Glaeser & Glendon, 1998; Jiobu & Curry, 2001; Williams & McGrath, 1976). Unfortunately, all of these studies have been unable to tease out the causal ordering of these relationships suggesting that the victimization experience might cause individuals to own a firearm or gun ownership that might assist the individual in avoiding a victimization experience. Despite limited evidence to the contrary (see McDowall & Wiersema, 1994), carrying a firearm in reaction to experiencing a traumatic experience or for self-protection

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has been found to be a typical human response. Criminologists have reported that some victims typically react to their fears of their victimization experience by purchasing and carrying a handgun. Specifically, respondents perceiving their neighborhood as a greater risk were more likely to own a gun and report intentions of purchasing a gun in the near future (Kleck, Kovandzic, Saber, & Hauser, 2011). More recently, scholars have traced increased levels of carrying a firearm to traumatic events that were not directly experienced by the victim. For example, using data from the National Longitudinal Study of Adolescent Health (Add Health), Barnes, Beaver, and Boutwell (2013) found a Gene × Environment (G × E) interaction (experiencing the 9/11 terrorist attacks and a polymorphism in the 5-HTTLPR gene) on carrying a firearm. These findings suggest that experiencing fear, either directly or indirectly, corresponds with a higher probability to carry a firearm. Recurring victimizations at the hands of a bully could be one such source of fear that corresponds with an increase in the probability to carry a firearm.

Current Focus Research interest into the factors associated with gun carrying persists despite sustained decreases in violence, in general, and homicide rates, more specifically. Research has historically documented how persistent victimizations have the potential to increase fear and result in a greater proclivity for victims to carry a firearm (see Lizotte & Bordua, 1980). Evidence is also beginning to emerge suggesting that victims of bullying possess a higher likelihood of carrying a firearm (Nansel et al., 2003). Despite these scientific contributions, several limitations in the extant research could potentially explain the equivocal findings as they relate to the association of bully victimizations and gun carrying. First, in several studies, the reference period documenting bully victimizations and gun carrying was restricted to a narrow period of the life course. For example, Brockenbrough and her colleagues measured victimization and gun carrying at one point in time, “over the last month,” in a student sample of 7th, 9th, and 11th graders (Brockenbrough, Cornell, & Loper, 2002). Using the reference period “during the current academic term,” Nansel and her colleagues investigated the effects of bullying and bully victimizations on gun carrying among a cross-sectional study of youths in Grades 6 through 10 (Nansel et al., 2003). Wong and Schonlau (2013) captured victimization experiences occurring only before the age of 12. These restrictions in the measurement period of the victimization and gun-carrying measures result in a significant underestimation of the true prevalence of these behaviors as they evolve over the life course. As a result of this, individuals victimized outside of these reference periods go unaccounted for and relationships could potentially go undocumented. Second, several studies have used cross-sectional research designs or measured exogenous and endogenous variables with overlapping reference periods resulting in difficulties in establishing the temporal ordering of the hypothesized relationships (Brockenbrough et al., 2002; Nansel et al., 2003). Finally, only one study has investigated the effects of bully victimizations on gun carrying while taking into account an

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individual’s preexisting involvement in gun carrying (Wong & Schonlau, 2013). Without controlling for prior involvement in carrying a gun, it becomes difficult to ascertain whether the victimization experience is a cause of gun carrying or whether these behaviors are the continuation of gun-carrying experiences occurring prior to the victimization experience. The present study uses data from the NLSY97 to build on the current research exploring the association between repeat bully victimizations and carrying a gun. Specifically, this study investigated the association of repeat bully victimizations occurring from birth to age 18 with the respondent’s likelihood of carrying a gun in adolescence and adulthood while controlling for several known predictors of gun carrying as well as preexisting gun carrying experiences. To accomplish this objective, two measures of repeat bully victimizations were assessed: (a) a dichotomous measure of repeat bully victimizations occurring before the age of 12, and (b) a categorical measure of repeat bully victimizations occurring up to the age of 18. These measures were then associated with three gun-carrying measures collected when respondents were adolescents and adults. Specifically, we test the following hypotheses: Hypothesis 1: Controlling for prior gun-carrying experiences, being a victim of repeated bully victimizations in childhood and adolescence corresponds with a higher probability of carrying a firearm. Hypothesis 2: Controlling for prior gun-carrying experiences, chronic bullyvictims (those individuals who were repeatedly victimized by a bully during childhood and adolescence) are more likely to carry a firearm than individuals victimized during only one of those developmental periods. If being repeatedly victimized by bullies leads to or exacerbates gun carrying after taking into account the confounding effect of prior carrying behaviors and several other potential confounding factors, our study would support intervention programs that aim to prevent bullying behaviors to limit their subsequent effects on carrying a firearm.

Method Subjects in this study were drawn from the NLSY97, a prospective household-based panel longitudinal study supported by the U.S. Department of Labor and the Bureau of Justice Statistics (Moore, Pedlow, Krishnamurty, & Wolter, 2000). Briefly, the NLSY97 is a nationally representative, longitudinal survey of individuals born between 1980 and 1984 who were living in the United States in 1997. The subjects selected into the NLSY97 were between the ages of 12 and 16 at Wave 1. The main goal of the NLSY97 was to collect information on the labor market experiences of youth as they transition from adolescence into adulthood; however, several measures related to the field of criminal justice were included in the survey protocol. Data collection continues to occur on an annual basis with Wave 14 (in year 2010) being the most recent wave available to the public. The overall retention rate over the 14 waves of data collection is 83.2%.

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The NLSY97 sample comprises two subsamples: (a) a cross-sectional sample (n = 7,335) and (b) a supplemental sample that oversamples for African Americans and Hispanics (n = 2,473). The cross-sectional sample was designed to be a self-weighting representation of U.S. households with adolescents between the ages of 12 and 16 as of December 31, 1996. The present analysis is based on self-reported data from the cross-sectional NLSY97 sample of 7,335 youth. A significant majority of these youth (n = 6,748; 92%) participated in the first round of surveys that were conducted in 1997 and 1998. The survey methodology allowed individuals who participated in the first round to miss one or more waves of data collection and still remain in the study. Only individuals within the cross-sectional sample who provided valid interviews across each of the waves of data under analysis (n = 6,641) were included in the subsequent analyses. Research has indicated that attritors in the NLSY97 tend to have higher earnings and wage rates than those respondents who remained in the survey (Aughinbaugh & Gardecki, 2007). Analyses across race and sex revealed that a significantly higher proportion of males were missing (t = 2.24; p = .025). No significant differences emerged in the analysis across categories of race.

Dependent Variables Gun-carrying prevalence: Since the date of the last interview.  Beginning in Wave 2, individuals responded to the following question: “Have you ever carried a gun since the date of last interview on [date of last interview]? When we say handgun, we mean any firearm other than a rifle or shotgun.” Response categories were designated as 0 = no and 1 = yes. Based on the respondent’s answers, we compiled a history of what is known about each individual’s approximately 12-month gun-carrying status from Wave 2 when participants were between the ages of 13 and 17 to Wave 14 when participants were between the ages of 25 and 29. Gun-carrying prevalence: Last 30 days.  During each wave, individuals acknowledging that they carried a handgun responded to the following question: “How many days have you carried a gun in the last 30 days?” Respondents reported a value between 0 and 30. To measure the 30-day gun-carrying prevalence rate, responses greater than zero were collapsed, so that those reporting 0 = did not carry in the last 30 days and those reporting greater than 0 = carried in the last 30 days. When the items from each wave were combined, the result was the cumulative prevalence rate of individuals who carried a gun in the last 30 days. Gun-carrying prevalence: To school in the last 30 days.  During each wave, individuals acknowledging that they carried a handgun in the last 30 days responded to the following question: “In the last 30 days, did you carry the handgun to school?” Response categories were designated as 0 = no and 1 = yes. When the items from each wave were combined, the result is the cumulative prevalence rate of individuals who carried a handgun to school in the last 30 days.

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Independent Variables Repeat bully victimization classifications. Two measures of repeat bully victimization were used in the analyses. The first measure documents individuals who experienced repeat bully victimizations from birth to the age of 12. At Wave 1, subjects were asked if they had “been a victim of repeated bully victimizations before the age of 12.” Response categories were designated as 0 = no and 1 = yes. A total of 20.0% of the sample reported experiencing repeat bully victimizations before the age of 12. The second measure documents individuals who experienced repeat bully victimizations from birth to the age of 18. During each of the next five waves (beginning in Wave 3), subjects who reached the age of 18 since the prior survey administration were asked whether they “had been a victim of repeated bully victimizations since they had turned age 12.” Response categories were designated as 0 = no and 1 = yes. Combining these questions with the initial repeat bully victimization item taken at Wave 1 created a four-category victimization measure. Specifically, individuals indicating that they had never been victimized across each wave were categorized as “non-victims” (73.7% of the sample), individuals experiencing repeat bully victimizations before the age of 12 only were categorized as “childhood victims” (14.7% of the sample), individuals experiencing repeat bully victimizations after the age of 12 only were categorized as “adolescent victims” (6.2% of the sample), and individuals who experienced repeat bully victimizations before and after the age of 12 were categorized as “chronic victims” (5.4% of the sample). Preexisting gun-carrying experiences.  At Wave 1, individuals responded to the following question: “Have you ever carried a handgun? When we say handgun we mean any firearm other than a rifle or shotgun.” Response categories were designated as 0 = no and 1 = yes. During each of the subsequent waves, respondents who were not interviewed or refused to answer the question at Wave 1 received this question again. The preexisting gun-carrying experiences variable represents a control for any involvement in gun carrying that may have occurred prior to the outcomes described below. Respondent gang involvement.  Research has documented a clear and positive relationship between being a member of a gang and carrying a firearm (Spano, Freilich, & Bolland, 2008). At Wave 1, individuals responded to the following question: “Have you ever belonged to a gang?” Response categories were designated as 0 = no and 1 = yes.” This variable measures whether individuals belonged to a gang. Neighborhood and school gang presence.  Evidence suggests that individuals living in disadvantaged neighborhoods in the presence of gangs have a higher probability of carrying a firearm (Duncan, 1996). At Wave 1, individuals responded to the following question: “Are there any gangs in your neighborhood or where you go to school? By gangs, we mean a group that hangs out together, wears gang colors or clothes, has set clear boundaries of its territory or turf, protects its members and turf against other rival gangs through fighting or threats.” Response categories were designated as 0 = no and

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1 = yes. This variable measures whether individuals observed gangs in their school or neighborhood. Peer involvement in gangs.  Peer involvement in carrying a gun and membership within a gang has been found to positively increase individual involvement in carrying a firearm (Lizotte, Krohn, Howell, Tobin, & Howard, 2000). At Wave 1, individuals responded to the following question: “What percent of your peers belong to a gang that does illegal activities?” Response categories were designated as 1 = almost none (less than 10%), 2 = about 25%, 3 = about half (50%), 4 = about 75%, and 5 = almost all (more than 90%). Higher scores on this measure are indicative of individuals who reported a greater proportion of their friends belonging to a gang.

Control Variables Two additional control variables were included in the analysis. The respondent’s sex was coded as 0 = female and 1 = male, and racial/ethnic background was coded as 0 = White and 1 = non-White.

Statistical Analysis The associations between repeated bully victimization variables and the gun-carrying variables were estimated using two approaches. First, we use multivariate logistic regression where we controlled for an individual’s preexisting gun-carrying experiences as well as included several known covariates of gun carrying in the multivariate models. Associations were quantified by calculating odds ratios (ORs) with 95% confidence intervals (CIs). The standard level of statistical significance was p < .05. Children in the non-victim category were always used as the reference group. Second, we use propensity score matching (PSM) that allows us to match victims with nonvictims to estimate the impact that the victimization had on carrying a gun. PSM adjusts for bias due to baseline differences in the treatment (bullied) and control (nonbullied) groups. All statistical analyses were performed using SAS version 9.2 (SAS Institute, Inc., Cary, NC) and R version 3.0.3 (“Warm Puppy”; Sekhon, 2011).

Findings Table 2 provides the descriptive characteristics of the sample. All of the subjects at Wave 1 were adolescents (average age = 13.98). By Wave 14, all of the subjects were clearly categorized as adult status (average age = 27.02). Just over half (51%) of the sample was male and these subjects were distributed across racial ethnic background proportionate to their presence in the population where 16.2% were African American, 13.8% Hispanic, and 70.0% Caucasian. Over the 14 waves of data collection, just over one fourth (28%) of the sample reported carrying a gun at some point in their life, 24% carried a handgun in the past 12 months, 13% carried a handgun in the past 30 days, and 1% carried a handgun to school.

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Table 2.  Descriptive Statistics of National Longitudinal Survey of Youth 1997 (N = 6,641). Measure Age (Wave 1) Age (Wave 14) Gender (1 = male) Race   African American  Hispanic  Caucasian Gangs in the neighborhood (1 = yes) Percent peers belong to a gang   Almost none (less than 10%)   About 25%   About half (50%)   About 75%   Almost all (more than 90%) Respondent belonged to a gang (1 = yes) Repeat bully victim—childhood (1 = yes) Repeat bully victim  Non-victim   Childhood victim   Adolescent victim   Chronic victim Ever carry a handgun (1 = yes) Carry a handgun in the past 12 months (1 = yes) Carry a handgun in the past 30 days (1 = yes) Carry a handgun to school (1 = yes)

Mean/prevalence

SD

Range

13.98 27.02 0.51

1.40 1.38 0.50

16.2 13.8 70.0 0.42

— — — 0.49

69.4 19.4 6.7 2.8 1.7 0.05 0.20

— — — — — 0.21 0.40

74.1 14.6 6.1 5.3 0.28 0.24 0.13 0.01

— — — — 0.45 0.43 0.33 0.09

12-16 25-29 0-1 0-2 — — — 0-1 0-4 — — — — — 0-1 0-1 0-3 — — — — 0-1 0-1 0-1 0-1

Bivariate Analysis Table 3 reports how prevalence estimates of carrying a gun significantly vary across several characteristics. Over one third (36.1%) of males carried a gun in the past 12 months compared with only 1 in 10 females (10.9%). This 3:1 ratio increased as the bounding period of the gun-carrying measure became more recent (19.8%-5.2%) and was located within the schools (1.4%-0.1%). The prevalence of gun-carrying differences was not replicated across categories of race where only the school prevalence measure significantly varied as African Americans (1.5%) and Hispanics (1.2%) reported significantly higher prevalence rates than Whites (0.6%). Research has consistently documented higher prevalence rates of gun carrying being associated with various measures of gang membership and association with known gang members (Bjerregaard & Lizotte, 1995). Respondents identifying a greater presence of gangs in their neighborhood, a higher proportion of their peers belonging to a gang, and a greater involvement themselves in a gang reported significantly higher gun-carrying

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Table 3.  Prevalence of Repeat Bully Victimization and Gun-Carrying Variables. 12-month gun30-day gun-carrying 30 day gun carrying carrying prevalence prevalence to school prevalence

Characteristic Gender  Female  Male Race   African American  Hispanic  Caucasian Gangs in the neighborhood  No  Yes Percent peers belong to a gang   Almost none (less than 10%)   About 25%   About half (50%)   About 75%   Almost all (more than 90%) Respondent belonged to a gang  No  Yes Repeat bully victim— childhood  No  Yes Repeat bully victim  Non-victim   Childhood victim   Adolescent victim   Chronic victim

χ2 = 583.64; p = .00 χ2 = 316.13; p = .00 10.9 5.2 36.1 19.8 χ2 = 0.98; p = .81 χ2 = 1.73; p = .63 24.8 12.6 22.3 12.6 23.9 12.9 χ2 = 7.89; p = .00 χ2 = 37.53; p = .00 21.2 11.8 27.6 14.1 χ2 = 41.39; p = .00 χ2 = 13.38; p = .01

χ2 = 35.36; p = .00 0.1 1.4 χ2 = 10.14; p = .02 1.5 1.2 0.6 χ2 = 0.99; p = .20 0.7 0.9 χ2 = 5.46; p = .24

22.1

11.9

0.6

25.3 31.0 35.5 33.6

13.7 15.7 18.0 16.1

0.8 1.2 1.7 1.8

χ2 = 95.15; p = .00

χ2 = 33.93; p = .00

χ2 = 18.52; p = .00

22.7 46.5 χ2 = 47.03; p = .00

12.1 23.3 χ2 = 23.12; p = .00

0.7 2.9 χ2 = 2.07; p = .11

21.9 30.9 χ2 = 20.13; p = .00 12.6 18.2 14.4 13.4

11.7 16.6 χ2 = 9.01; p = .03 7.9 10.7 6.7 7.6

0.7 1.1 —        

prevalence rates on most of the measures. Specifically, 12-month and 30-day prevalence rates were significantly higher for those reporting a gang presence in their neighborhood and self-identifying as having a greater proportion of their peers belonging to a gang. Respondent involvement in a gang significantly corresponded with gun-carrying prevalence rates that were greater than twice those of non-gang members. Finally, respondents identifying that they experienced repeat bully victimizations consistently reported higher gun-carrying prevalence rates. Compared with non-victims, childhood

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Turner et al. Table 4.  Unadjusted and Adjusted ORs of Gun-Carrying Behaviors and Repeat Bully Victimization in Childhood.

Bullying category

Subjects (N = 6,641)

12-month gun-carrying prevalence

No control for preexisting gun carrying  Non-victims 5,314 1 [reference]  Victims 1,327 1.3 [1.1, 1.5]*** Controlling for preexisting gun carrying  Non-victims 5,314 1 [reference]  Victims 1,327 1.3 [1.1, 1.5]**

30-day gun-carrying prevalence

30-day gun carrying to school prevalence

OR [95% CI]

OR [95% CI]

1 [reference] 1.3 [1.1, 1.5]**

1 [reference] 1.2 [0.6, 2.2]

1 [reference] 1.2 [1.0, 1.5]*

1 [reference] 1.0 [0.5, 2.0]

Note. Results are of the multivariate logistic regressions adjusting for respondent’s sex, racial/ethnic background, gang presence in the neighborhood, percent of peers belonging to a gang, and the respondent’s involvement in a gang. Estimates in the bottom panel additionally controlled for prior gun carrying. OR = odds ratio; CI = confidence interval. *p < .05. **p < .01. ***p < .001.

victims of bullying reported significantly higher 12-month gun-carrying prevalence rates (30.9%-21.9%) and significantly higher 30-day gun-carrying prevalence rates (16.6%-11.7%). When the repeat bully victimization measure was extended into adolescence, significant differences in the 12-month and 30-day gun-carrying prevalence measures remained with childhood victims consistently reporting the highest rates.

Multivariate Analysis Focusing on the effects of repeat bully victimizations experienced during childhood, results from the multivariate logistic regression analyses indicate a consistent pattern across the various measures of gun carrying in adolescence and adulthood (see Table 4). Although both sets of models controlled for gender, racial/ethnic background, and each of the three gang affiliation measures, only those in the bottom panel controlled for preexisting gun carrying. When preexisting gun carrying was not taken into account, experiencing repeat bully victimizations in childhood was associated with greater odds of carrying a gun in adolescence and adulthood in the past 12 months and in the past 30 days. This relationship was not replicated in the gun carrying to school measure. In the models controlling for preexisting gun carrying, the nature of the relationships remained the same although the magnitude of the ORs for the 30-day guncarrying measure slightly decreased owing to the correlation with the repeat bully victimization measure. Turning the focus on the effects of repeat bully victimizations experienced over a longer period of the life course, results from the multivariate logistic regression analyses provide a slightly different picture (see Table 5). Similar to the strategy in the prior

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Table 5.  Unadjusted and Adjusted ORs of Gun-Carrying Behaviors and Repeat Bully Victimization in Childhood and Adolescence.

Bullying category

Subjects (N = 6,240)

No control for preexisting gun carrying  Non-victims 4,620   Childhood victims 906   Adolescent victims 382   Chronic victims 332 Control for preexisting gun carrying  Non-victims 4,620   Childhood victims 906   Adolescent victims 382   Chronic victims 332

12-month guncarrying prevalence

30-day gun-carrying prevalence

OR [95% CI]

OR [95% CI]

1 [reference] 1.3 [1.0, 1.5]* 1.1 [0.8, 1.5] 0.9 [0.7, 1.3]

1 [reference] 1.2 [0.9, 1.5] 0.8 [0.5, 1.2] 0.8 [0.5, 1.3]

1 [reference] 1.2 [1.0, 1.5]* 1.1 [0.8, 1.5] 0.9 [0.7, 1.3]

1 [reference] 1.1 [0.9, 1.4] 0.8 [0.5, 1.2] 0.8 [0.5, 1.3]

Note. Results are of the multivariate logistic regressions adjusting for respondent’s sex, racial/ethnic background, gang presence in the neighborhood, percent of peers belonging to a gang, and the respondent’s involvement in a gang. Estimates in the bottom panel additionally controlled for prior gun carrying. OR = odds ratio; CI = confidence interval. *p < .05.

analysis, both sets of models controlled for gender, racial/ethnic background, and each of the three gang affiliation measures; only the models in the bottom panel controlled for preexisting gun carrying. Regardless of whether preexisting gun carrying is controlled, only childhood victims of bullying reported significantly higher odds of carrying a gun for the 12-month measure documented in adulthood. Compared with non-victims, those experiencing repeat bully victimizations during adolescence only or during adolescence and childhood did not report significantly higher odds of carrying a gun in adulthood.

Propensity Score Matching To further investigate the effect of repeat bully victimizations on gun carrying, we conducted a PSM analysis. This strategy is a quasi-experimental design that approximates the conditions of an experiment in the absence of random assignment, but allows for the estimation of a treatment effect. Grounded in the logic of counterfactual estimation, PSM uses a selection on observables approach to match cases in the treatment condition to cases in the untreated condition to serve as a counterfactual (Apel & Sweeten, 2010). Treatment can be considered to be any intentional intervention, and a propensity score can be defined as “the conditional probability of assignment to a particular treatment, given a vector of observed covariates” (Rosenbaum & Rubin, 1983, p. 41). Cases can then be matched based on this conditional probability to create

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a balance between treated and untreated cases. Having demonstrated balance on the variables included in the estimation of the propensity score, the researcher can assume that treatment is “as good as randomly assigned” (Rosenbaum & Rubin, 1983, p. 41; Shadish, Cook, & Campbell, 2002). Using the NLSY97 sample described above, we use PSM to estimate the average treatment effect (ATE) of repeat bullying on gun carrying. More specifically, we estimate the ATE of four treatments as independent variables: having ever been a repeat bullying victim, having been a childhood victim of repeat bullying, having been an adolescent victim of repeat bullying, and having been a chronic victim of repeat bullying. These treatments are defined as described above, and are coded dichotomously such that 0 = untreated and 1 = treated. For each of these four independent variables, we estimate the ATE on four dependent variables: gun-carrying prevalence (from Waves 2 to 14), gun-carrying prevalence in the last 12 months, gun carrying in the last 30 days, and gun carrying prevalence at school in the last 30 days. These measures are also defined and coded as described above. Because we estimate the ATE for each treatment condition for each gun-carrying permutation, below we perform a total of 16 PSM analyses. For each of the four treatments, we estimate the propensity score, P(xi), using the logistic distribution function: P(xi ) = exp [β0+β1(M)+β2(W)+β3(H)+β4(B)+β5(A)+β6(NG)+β7(PG)+β8(RG) ] 1+exp [β0+β1(M)+β2(W)+β3(H)+β4(B)+β5(A)+β6(NG)+β7(PG)+β8(RG) ]. In this specification, M, W, H, and B1 represent dichotomous indicators of whether the respondent is male, White, Hispanic, or Black, respectively; A is a continuous measure of the respondent’s age; NG is a dichotomous indicator of neighborhood or school gang presence; PG is an ordinal measure of peer gang involvement; and RG is a dichotomous indicator of the respondent’s gang involvement.2 The key output for this model of treatment status is the predicted probability of experiencing the particular form of repeat bullying under consideration, which is used as the propensity score for the matching procedure. Table 6 shows the results of these logistic regression models. The model predicting the probability of ever being a repeat bully victim (see Table 6) indicates that repeat bullying victims are more likely to be male, more likely to have gang presence in their neighborhoods or schools, have higher rates of peer gang involvement, and are more likely to belong to gangs themselves. The model predicting the probability of being a childhood repeat bully victim indicates that childhood repeat bullying victims are more likely to be male, likely to be older, more likely to have gang presence in their neighborhoods or schools, have higher rates of peer gang involvement, and are more likely to belong to gangs themselves. The model predicting the probability of being a repeat bully victim in adolescence indicates that adolescent repeat bullying victims are more likely to be Hispanic or Black, and are likely to be older. The model predicting the probability of being a chronic repeat bullying victim indicates that victims are more likely to be Hispanic, older, more likely to have gang presence in their neighborhoods or schools, and more likely to have higher rates of peer gang involvement.

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Table 6.  Propensity Score Models for Bullying Treatment Conditions. Logit model estimates Treatment condition

Variable Male White Hispanic Black Age Neighborhood gangs Peers in gangs Gang membership (Intercept)

Ever being repeatedly bullied

Childhood repeat bullying

Adolescent repeat bullying

Chronic repeat bullying

b (SE)

b (SE)

b (SE)

b (SE)

0.096 (0.099) −0.582 (0.384) −0.859 (0.395)* −0.955 (0.392)* −0.179 (0.036)*** 0.027 (0.107)

0.168 (0.108) −0.038 (0.476) −1.034 (0.494)* −0.596 (0.484) −0.209 (0.040)*** 0.569 (0.117)***

0.267 (0.053)*** 0.032 (0.268) −0.440 (0.272) −0.114 (0.271) −0.021 (0.019) 0.398 (0.058)***

0.301 (0.065)*** 0.520 (0.403) 0.282 (0.407) 0.654 (0.405) 0.123 (0.024)*** 0.381 (0.071)***

0.131 (0.028)*** 0.095 (0.034)** 0.102 (0.053) 0.153 (0.055)** 0.355 (0.111)** 0.616 (0.123)*** −0.460 (0.260) −0.016 (0.223) 40.068 (38.192) −246.345 (47.148)*** 352.495 (72.031)*** 411.617 (79.396)***

Note. N = 6,240. *p < .05. **p < .01. ***p < .001.

The distributions of the propensity scores for treated and untreated cases are displayed in Figure 1. Considering each treatment condition separately, we have plotted the proportion of treated and untreated cases in each of 20 equally sized bins. As seen in the figure, there is a substantial overlap between treated and untreated cases in each of the four bullying conditions, demonstrating common support. To further evidence the balance on included covariates between treated and untreated cases, we include the standardized bias (SB) in Table 7 before and after matching.3 By convention, covariates with |SB| ≥ 20 are considered imbalanced, but a stricter criterion of |SB| ≥ 10 is sometimes used. Using the |SB| ≥ 10 criterion, in Table 7 (ever being repeatedly bullied) we can see that prior to matching, five covariates are imbalanced; (childhood repeat bulling) six covariates are imbalanced prior to matching; (adolescent repeat bullying), three covariates are imbalanced prior to matching; and (chronic repeat bullying) five covariates are imbalanced prior to matching. Regardless of whether 20 or 10 is chosen as the threshold for indicating balance, Table 7 shows that all covariates are balanced after matching in each bullying treatment condition. We provide estimates of the ATE of each of the bullying conditions on four guncarrying measures in Table 8. For robustness, we estimate the ATE4 for each gun-carrying outcome using three model specifications. We estimate the ATE using a one-to-one nearest neighbor match with no caliper, a three-to-one nearest neighbor match with no caliper, and a five-to-one nearest neighbor match with no caliper. Results from these models are remarkably consistent across model specification. This consistency supports the notion that the results are not contingent on the choice of

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Figure 1.  Propensity score distribution by treatment status.

matching strategy. The PSM models show that the ATE for ever being a repeat bullying victim on ever carrying a gun is estimated to be 0.036 and is highly significant. Thus, one would expect an increase in probability of ever carrying a gun of 3.6% points had all subjects been a repeat bullying victim, a small but significant effect. The estimates of the ATE for ever being a victim of repeat bullying victim on carrying a gun in the last year ranges from 0.029 to 0.031, and is also highly statistically significant. This impact is substantively much larger, representing an effect of a roughly 3% increase in the probability of carrying a gun in the last year. These results suggest that repeat bullying has an effect on ever carrying a gun and carrying a gun in the last year. The ATEs for ever being a repeat bullying victim on the other gun-carrying outcomes are not significantly different from zero, indicating that this form of bullying does not have an effect on gun carrying in the last month, or carrying a gun to school in the last month. The results for childhood repeat bullying are also quite consistent. In estimating the effect on ever carrying a gun, the ATEs range from 0.036 to 0.040 and are statistically significant. Similarly, the ATEs of childhood repeat bullying on gun carrying in the last year range from 0.024 to 0.029 and are statistically significant.5 Thus, childhood repeat bullying has an effect on ever carrying a gun and carrying a gun in the last year.

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Table 7.  Balance Diagnostics Before and After Matching for Bullying Treatment Conditions. Balance diagnostics: SB before and after matching Treatment condition Ever being repeatedly bullied Variable Male White Hispanic Black Age Neighborhood gangs Peers in gangs Gang membership

Childhood repeat bullying

Adolescent repeat bullying

Chronic repeat bullying

Before After Before After Before After Before After matching matching matching matching matching matching matching matching 13.616 6.666 −11.795 2.503 −5.798 22.734

−0.326 0.054 −0.352 0.570 0.758 1.880

16.075 −4.707 −6.231 11.302 13.622 22.647

−1.577 4.034 −1.211 −2.108 −0.229 2.345

3.753 12.575 −5.880 −11.711 −24.328 2.755

1.575 −2.678 7.804 −3.517 −2.409 4.072

7.787 26.119 −27.221 −9.333 −29.187 28.697

−6.424 8.574 −6.244 −2.748 4.236 0.544

16.586 12.419

−1.620 −1.798

15.586 17.268

−0.904 −2.912

6.680 −7.625

−9.664 −9.361

17.423 5.959

−9.115 −1.896

Note. SB = standardized bias.

However, the ATEs for childhood repeat bullying on the remaining gun carrying outcomes are not significantly different from zero, indicating that childhood repeat bullying does not have an effect on gun carrying in the last month, or carrying a gun to school in the last month. The results for adolescent repeat bullying are somewhat divergent from the results presented thus far. The ATEs for adolescent repeat bullying on ever carrying a gun, carrying a gun in the last year, and carrying a gun to school do not reach statistical significance. However, the ATEs for adolescent repeat bullying on carrying gun in the last month are tightly clustered between 0.036 and 0.038,6 and are highly statistically significant. These results lead us to conclude that adolescent repeat bullying has a nonzero effect on gun carrying in the last month, a more temporally proximate measure. Our estimates of the ATEs for being a chronic repeat bully victim are much less consistent. The majority of the ATEs are statistically indistinguishable from zero. The exception is the ATE of chronic repeat bullying on gun carrying in the last year when a one-to-one nearest neighbor matching protocol is used. Although the ATE for the same treatment on the same outcome is significant at the p < .10 level using a three-toone nearest neighbor matching protocol, this estimate does not reach the conventional level for statistical significance of p < .05. We conclude that the significant result found in the one-to-one nearest neighbor model is likely due to chance, and conclude that chronic repeat bullying does not have an effect on any of the gun-carrying outcomes considered. However, it bears mentioning that the sample included only 3327 chronic repeat bullying victims in a sample of 6,240 respondents, so our analyses may lack the statistical power to detect a non-zero effect.

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Turner et al. Table 8.  Average Treatment Effect of Bullying Treatment Conditions on Gun-Carrying Outcomes. Outcome

Model specification Treatment condition

Ever carrying a gun

Carrying a gun in the last year

Carrying a gun in the last month

Carrying a gun to school

ATE (SE)

ATE (SE)

ATE (SE)

ATE (SE)

0.029 (0.011)**

0.009 (0.008)

0.001 (0.002)

0.029 (0.011)**

0.010 (0.008)

0.001 (0.003)

0.031 (0.011)**

0.011 (0.008)

0.001 (0.003)

0.029 (0.014)*

0.011 (0.011)

−0.001 (0.003)

0.027 (0.014)*

0.010 (0.011)

−0.001 (0.003)

0.024 (0.014)†

0.008 (0.011)

−0.002 (0.003)

−0.008 (0.023)

0.036 (0.011)**

−0.001 (0.005)

−0.013 (0.024)

0.036 (0.011)**

0.003 (0.006)

−0.008 (0.023)

0.038 (0.012)**

0.004 (0.006)

Ever being repeatedly bullied   1 nearest neighbor, no 0.036 (0.011)** caliper   3 nearest neighbors, 0.036 (0.011)** no caliper   5 nearest neighbors, 0.036 (0.012)** no caliper Childhood repeat bullying   1 nearest neighbor, no 0.040 (0.015)** caliper   3 nearest neighbors, 0.038 (0.015)* no caliper   5 nearest neighbors, 0.036 (0.015)* no caliper Adolescent repeat bullying   1 nearest neighbor, no −0.019 (0.024) caliper   3 nearest neighbors, −0.026 (0.024) no caliper   5 nearest neighbors, −0.014 (0.024) no caliper Chronic repeat bullied   1 nearest neighbor, no 0.055 (0.030) caliper   3 nearest neighbors, 0.052 (0.029) no caliper   5 nearest neighbors, 0.041 (0.029) no caliper

0.059 (0.029)*

0.005 (0.021)

−0.001 (0.006)

0.052 (0.028)†

−0.004 (0.020)

−0.001 (0.006)

0.041 (0.028)

−0.013 (0.019)

−0.001 (0.006)

Note. N = 6,240. ATE = average treatment effect. †p < .10.*p < .05. **p < .01.

Discussion Several highly publicized incidents have been documented where youths who were the victims of repeat bullying incidents subsequently commit a variety of violent acts. These acts have primarily taken the form of either (a) the victim turning into the aggressor and retaliating against the bully and/or other innocent victims (Olweus, 2011; Sourander, Jensen, Ronning, Elonheimo, et al., 2007; Sourander et al., 2009), or (b) the victim experiencing severe psychological distress and engaging in self-inflicted harm or taking his or her own life (Copeland, Wolke, Angold, & Costello, 2013; Kaltiala-Heino, Rimpela, Marttunen, Rimpela, & Rantanen, 1999; Klomek et al., 2007; Klomek et al.,

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2008; Klomek et al., 2009; Kumpulainen & Rasanen, 2000; Sourander, Jensen, Ronning, Niemela, et al., 2007; van der Wal et al., 2003). The most tragic and highly publicized cases often result in the victim having access to, and making use of, a firearm or other lethal weapon to inflict harm onto other individuals. Notwithstanding these empirical facts, it remains unclear the extent to which repeat bully victimizations might be associated with carrying a gun. The extant research investigating this relationship has been equivocal but it has also been plagued by three notable limitations: (a) measures of victimization and gun carrying over a limited period of the life course, (b) limited inclusion of potential confounding variables, and (c) no controls for preexisting gun-carrying experiences (Andershed et al., 2001; Brockenbrough et al., 2002; Glew et al., 2008; Haddow, 2006; Nansel et al., 2003; Stein et al., 2007). This last point is particularly important given that failure to account for prior gun-carrying behaviors limits reasonable inferences about the direction of the observed association. The present longitudinal study sheds light on this issue by examining the association of repeat bully victimizations experienced over an 18-year period with the gun-carrying behaviors of adolescents and adults. Several important findings have emerged from these efforts. First, the results across the two sets of analyses are more similar than they are different from one another. Second, when the repeat bully victimization was dichotomized, victims were more likely to ever carry a firearm and carry a firearm in the last 30 days only. No support emerged suggesting that the victim of repeat bullying had a higher probability to carry a firearm to school in the last 30 days. Third, in both sets of analyses, children who are repeatedly victimized by a bully are more likely to carry a gun since the date of the last interview and in the last 30 days. Fourth, empirical support was found for the association between adolescent victimization and gun carrying in adulthood only using the PSM method. Finally, no empirical support was found suggesting that chronic victims were at an increased likelihood of carrying a firearm. It could be possible that chronic victims are more likely to react via methods of self-harm versus being more likely to carry a firearm. In fact, the extant research has documented a victimization/selfharm relationship (see Turner et al., 2013). Combined, these findings suggest that being a repeat victim of bullying in childhood was associated with an increased likelihood of ever carrying a firearm; however, being a repeat victim of bullying in adolescence was associated with carrying a firearm more proximate to the interview period. Findings from this study suggest that programs designed to reduce bullying and bully victimizations could potentially affect other violent outcomes (i.e., gun carrying) that may evolve later in the life course. In addition, the data in the present study suggest that the impact of these intervention programs would probably be stronger in childhood (where the results were more consistent and stronger) versus adolescence. This implication is consistent with the long line of research documenting that children exposed to interventions early in the life course experience lower levels of delinquency as adolescents and arrest as adults (Olds et al., 1998; Piquero, Farrington, Welsh, Tremblay, & Jennings, 2009; Reynolds, Temple, Robertson, & Mann, 2001; Yoshikawa, 1995). Notwithstanding these policy implications, it is also important for parents, teachers, and even pediatricians to engage in discussions about bullying with youths

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and their families at annual well-checks early in the life course (Committee on Injury, Violence, and Poison Prevention, 2009). Although children may fear reporting victimizations to school staff, they may feel more comfortable discussing the events of victimization incidents with their pediatrician who is not directly involved with the incident (Unnever & Cornell, 2004). Several limitations of this study should be noted. First, the measure of repeat bully victimization is a retrospective item measured at ages 12 and 18 and is limited in capturing the short-term frequency of the victimization incident. So while including the word repeated in the terminology of the item implies that it was not an isolated occurrence, it is unclear how frequently individuals were victimized. Second, the NLSY97 did not include a bullying item. Because of this omission, it is unclear what proportion of the victims were also bullies. This is important because past research has documented that bully-victims generally report the highest odds of subsequent behavioral and psychological problems related to the bullying experience (Arseneault et al., 2006; Forero et al., 1999; Juvonen et al., 2003; Nansel et al., 2004; Nansel et al., 2001; Veenstra et al., 2005; Wolke et al., 2000). Third, as carrying a gun to school appears to be a relatively rare event (Rudatsikira, Singh, Job, & Knutsen, 2007), the 30-day reference period included in this item further limited the documentation of this behavior, which may have affected the probability of a significant relationship. Future research exploring gun carrying to school over a longer period of time would be beneficial in exploring the merits of this limitation. Fourth, the present study did not explore the mediating variables through which repeat bully victimizations could potentially affect whether individuals carry a firearm. We also encourage future researchers to explore whether victims choose to carry a gun for purposes of self-defense and retaliation on future bullies. Finally, in addition to focusing on victims of bullies, research needs to further investigate the causal factors related to bullying. Recent efforts relying on national-level data have identified the importance of childhood adversities and other psychiatric disorders that are associated with bullying (Vaughn et al., 2011; Vaughn et al., 2010). It remains to be seen the extent to which these correlates are also associated with carrying a firearm. This study provides an important contribution to the current body of literature on violence among youth. To date, we are unaware of another study that investigated the association of experiencing repeat bully victimizations experienced during an extended period of childhood and adolescence with the likelihood of carrying a gun during adolescence and adulthood while controlling for preexisting levels of gun carrying and several other potentially confounding variables. Results from this study indicate that compared with non-victims, childhood and adolescent victims of repeated bullying report higher prevalence rates of several measures of gun carrying. These associations, however, were dependent on the analytic tool and were not replicated for prevalence rates of carrying a gun to school. Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

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Funding The author(s) received no financial support for the research, authorship, and/or publication of this article.

Notes 1. Regarding ethnicity, those indicating “other” ethnicity are excluded as the reference category. 2. See above for precise definitions and coding of these measures. 3. The standardized bias figures are based on a one-to-one nearest neighbor match with no caliper. 4. The average treatment effect (ATE) is interpreted as the average difference in potential outcomes across the population (Apel & Sweeten, 2010). In other words, it is the difference in the outcome or dependent variable that would be expected if everyone in the population received treatment. 5. Childhood bullying therefore raises the average probability of ever carrying a gun by 3.6 to 4.0 percentage points, and the probability of carrying a gun in the last year by 2.4 to 2.9 percentage points. 6. An increase in the average probability of carrying a gun in the last month of 3.6 to 3.8 percentage points. 7. Although a large sample by the standards of conventional statistics, this is relatively small when considering the requirements of propensity score matching (PSM). PSM is often described as a “data hungry” technique (Heinrich, Maffioli, & Vazquez, 2010, p. 18), requiring a large pool of comparison units to serve as adequate matches.

References Andershed, H., Kerr, M., & Stattin, H. (2001). Bullying in school and violence on the streets: Are the same people involved? Journal of Scandinavian Studies in Criminology and Crime Prevention, 2, 31-49. Anderson, M., Kaufman, J., Simon, T. R., Barrios, L., Paulozzi, L., Ryan, G., . . . Potter, L. (2001). School-associated violent deaths in the United States, 1994-1999. Journal of the American Medical Association, 286, 2695-2702. Apel, R. J., & Sweeten, G. (2010). Propensity score matching in criminology and criminal justice. In A. Piquero, & D. Weisburd (Eds.), Handbook of quantitative criminology (pp. 543-562). New York, NY: Springer. Arseneault, L., Walsh, E., Trzesniewski, K., Newcombe, R., Caspi, A., & Moffitt, T. E. (2006). Bullying victimization uniquely contributes to adjustment problems in young children: A nationally representative cohort study. Pediatrics, 118, 130-138. Aughinbaugh, A., & Gardecki, R. (2007). Attrition in the National Longitudinal Survey of Youth 1997. Washington, DC: Bureau of Labor Statistics. Barnes, J. C., Beaver, K. M., & Boutwell, B. B. (2013). A functional polymorphism in a serotonin transporter gene (5-HTTLPR) interacts with 9/11 to predict gun-carrying behavior. PLoS ONE, 8(8), e70807. Bjerregaard, B., & Lizotte, A. J. (1995). Gun ownership and gang membership. Journal of Criminal Law and Criminology, 86, 37-58. Boey, C. C. M., & Goh, K. L. (2001). The significance of life-events as contributing factors in childhood recurrent abdominal pain in an urban community in Malaysia. Journal of Psychosomatic Research, 51, 559-562.

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Braga, A. (2012). Gun violence among serious offenders. Washington, DC: U.S. Department of Justice. Brockenbrough, K. K., Cornell, D. G., & Loper, A. B. (2002). Aggressive attitudes among victims of violence at school. Education & Treatment of Children, 25, 273-287. Cao, L., Cullen, F. T., & Link, B. G. (1997). The social determinants of gun ownership: Selfprotection in an urban environment. Criminology, 35, 629-658. Committee on Injury, Violence, and Poison Prevention. (2009). Role of the pediatrician in youth violence prevention. Pediatrics, 124, 393-402. Copeland, W. E., Wolke, D., Angold, A., & Costello, E. G. (2013). Adult psychiatric outcomes of bullying and being bullied by peers in childhood and adolescence. JAMA Psychiatry, 70, 419-426. Cunningham, P. B., Henggeler, S. W., Limber, S. P., Melton, G. B., & Nation, M. A. (2000). Patterns and correlates of gun ownership among nonmetropolitan and rural middle school students. Journal of Clinical Child Psychology, 29(3), 432-442. DeFronzo, J. (1979). Fear of crime and handgun ownership. Criminology, 17, 331-340. Duncan, D. F. (1996). Growing up under the gun: Children and adolescents coping with violent neighborhoods. Journal of Primary Prevention, 16, 343-356. Forero, R., McLellan, L., Rissel, C., & Bauman, A. (1999). Bullying behaviour and psychosocial health among school students in New South Wales, Australia: Cross-Sectional Survey. British Medical Journal, 319, 344-348. Glaeser, E. L., & Glendon, S. (1998). Who owns guns? Criminals, victims, and the culture of violence. American Economic Review, 88, 458-462. Glew, G. M., Fan, M., Katon, W., & Rivara, F. P. (2008). Bullying and school safety. Journal of Pediatrics, 152, 123-128. Glew, G. M., Fan, M., Katon, W., Rivara, F. P., & Kernic, M. A. (2005). Bullying, psychosocial adjustment, and academic performance in elementary school. Archives of Pediatrics & Adolescent Medicine, 159, 1026-1031. Haddow, J. L. (2006). Residual effects of repeated bully victimization before the age of 12 on adolescent functioning. Journal of School Violence, 5(2), 37-52. Haddow, J. L., & Haddow, J. L. (2006). Residual effects of repeated bully victimization before the age of 12 on adolescent functioning. Journal of school violence, 5(2), 37-52. Heinrich, C., Maffioli, A., & Vazquez, G. (2010). A primer for applying propensity-score matching (Impact-Evaluation Guidelines, Technical Notes, No. IDB-TN-161). Washington, DC: Office of Strategic Planning and Development Effectiveness, Inter-American Development Bank. Jiobu, R. M., & Curry, T. J. (2001). Lack of confidence in the federal government and the ownership of firearms. Social Science Quarterly, 82, 77-88. Juvonen, J., Graham, S., & Schuster, M. A. (2003). Bullying among young adolescents: The strong, the weak, and the troubled. Pediatrics, 112, 1231-1237. Kaltiala-Heino, R., Rimpela, M., Marttunen, M., Rimpela, A., & Rantanen, P. (1999). Bullying, depression, and suicidal ideation in Finnish adolescents: School survey. British Medical Journal, 319, 348-351. Kleck, G., Kovandzic, T., Saber, M., & Hauser, W. (2011). The effect of perceived risk and victimization on plans to purchase a gun for self-protection. Journal of Criminal Justice, 39, 312-319. Klomek, A. B., Marrocco, F., Kleinman, M., Schonfeld, I. S., & Gould, M. S. (2007). Bullying, depression, and suicidality in adolescents. Journal of the American Academy of Child & Adolescent Psychiatry, 46, 40-49.

Downloaded from ijo.sagepub.com at University of Manitoba Libraries on June 12, 2015

24

International Journal of Offender Therapy and Comparative Criminology 

Klomek, A. B., Sourander, A., Kumpulainen, K., Piha, J., Tamminen, T., Moilanen, I., . . . Gould, M. S. (2008). Childhood bullying as a risk for later depression and suicidal ideation among Finnish males. Journal of Affective Disorders, 109, 47-55. Klomek, A. B., Sourander, A., Niemela, S., Kumpulainen, K., Piha, J., Tamminen, T., . . . Gould, M. S. (2009). Childhood bullying behaviors as a risk for suicide attempts and completed suicides: A population-based birth cohort study. Journal of the American Academy of Child & Adolescent Psychiatry, 48, 254-261. Kumpulainen, K., & Rasanen, E. (2000). Children involved in bullying at elementary school age: Their psychiatric symptoms and deviance in adolescence. Child Abuse & Neglect, 24, 1567-1577. Laflamme, L., Engström, K., Möller, J., Alldahl, M., & Hallqvist, J. (2002). Bullying in the school environment: An injury risk factor? Acta Psychiatrica Scandinavica, 106(Suppl. 412), 20-25. Lichtblau, E., & Rich, M. (2012, December). N.R.A. envisions “a good guy with a gun” in every school. The New York Times. Retrieved from http://www.nytimes.com/2012/12/22/us/nracalls-for-armed-guards-at-schools.html?pagewanted=all Limber, S. P. (2002, May 3). Addressing youth bullying behaviors. In M. Fleming & K. J. Towey (Eds.), Proceedings from the Educational Forum on Adolescent Health: Youth Bullying (pp. 34-40). Chicago, IL: American Medical Association. Lizotte, A. J., & Bordua, D. J. (1980). Firearms ownership for sport and protection: Two divergent models. American Sociological Review, 45, 229-244. Lizotte, A. J., Krohn, M. D., Howell, J. C., Tobin, K., & Howard, G. J. (2000). Factors influencing gun carrying among young urban males over the adolescent-young adult life course. Criminology, 38, 811-834. Luster, T., & Oh, S. M. (2001). Correlates of male adolescents carrying handguns among their peers. Journal of Marriage and Family, 63(3), 714-726. Marciniak, L., & Loftin, C. (1991). Measuring protective handgun ownership. Criminology, 29, 531-540. McDowall, D., & Wiersema, B. (1994). The incidence of defensive firearm use by US crime victims, 1987 through 1990. American Journal of Public Health, 84, 1982-1984. Moore, W., Pedlow, S., Krishnamurty, P., & Wolter, K. (2000). National Longitudinal Survey of Youth 1997 (NLSY97) technical sampling report. Chicago, IL: National Opinion Research Center. Nansel, T. R., Craig, W., Overpeck, M. D., Saluja, G., & Ruan, J. (2004). Cross-national consistency in the relationship between bullying behaviors and psychosocial adjustment. Archives of Pediatrics & Adolescent Medicine, 158, 730-736. Nansel, T. R., Overpeck, M. D., Haynie, D. L., Ruan, W. J., & Scheidt, P. C. (2003). Relationships between bullying and violence among U.S. youth. Archives of Pediatrics & Adolescent Medicine, 157, 348-353. Nansel, T. R., Overpeck, M. O., Pilla, R. S., Ruan, W. J., Simons-Morton, B., & Scheidt, P. (2001). Bullying behaviors among U.S. youth: Prevalence and association with psychosocial adjustment. Journal of the American Medical Association, 285, 2094-2100. Olds, D., Henderson, C. R., Cole, R., Eckenrode, J., Kitzman, H., Luckey, D., . . . Powers, J. (1998). Long-term effects of nurse home visitation on children’s criminal and antisocial behavior: 15-year follow-up of a randomized controlled trial. Journal of the American Medical Association, 280, 1238-1244. Olweus, D. (2011). Bullying at school and later criminality: Findings from three Swedish community samples of males. Criminal Behaviour and Mental Health, 21, 151-156.

Downloaded from ijo.sagepub.com at University of Manitoba Libraries on June 12, 2015

25

Turner et al.

Piquero, A. R., Farrington, D. P., & Blumstein, A. (2003). The criminal career paradigm. Crime and Justice, 30, 359-506. Piquero, A. R., Farrington, D. P., Welsh, B. C., Tremblay, R., & Jennings, W. G. (2009). Effects of early family/parent training programs on antisocial behavior and delinquency. Journal of Experimental Criminology, 5, 83-120. Reynolds, A. J., Temple, J. A., Robertson, D. L., & Mann, E. A. (2001). Long-term effects on an early childhood intervention on educational achievement and juvenile arrest: A 15-year follow-up of low-income children in public schools. Journal of the American Medical Association, 285, 2339-2346. Rosenbaum, P. R., & Rubin, D. B. (1983). The central role of the propensity score in observational studies for causal effects. Biometrika, 70, 41-55. Rudatsikira, E., Singh, P., Job, J., & Knutsen, S. (2007). Variables associated with weaponcarrying among young adolescents in southern California. Journal of Adolescent Health, 40, 470-473. Sekhon, J. S. (2011). Multivariate and propensity score matching software with automated balance optimization: The matching package for R. Journal of Statistical Software, 42(7), 1-52. Shadish, W. R., Cook, T. D., & Campbell, D. T. (2002). Experimental and quasi-experimental designs for generalized causal inference. Wadsworth Cengage Learning. Sharp, S., Thompson, D., & Arora, T. (2000). How long before it hurts? School Psychology International, 21, 37-46. Simon, T. R., Dent, C. W., & Sussman, S. (1997). Vulnerability to victimization, concurrent problem behaviors, and peer influence as predictors of in-school weapon carrying among high school students. Violence and Victims, 12(3), 277-289. Sourander, A., Helstela, L., Helenius, H., & Piha, J. (2000). Persistence of bullying from childhood to adolescence: A longitudinal 8-year follow-up study. Child Abuse & Neglect, 24, 873-881. Sourander, A., Jensen, P., Ronning, J. A., Elonheimo, H., Niemela, S., Helenius, H., . . . Almqvist, F. (2007). Childhood bullies and victims and their risk of criminality in late adolescence. Archives of Pediatrics & Adolescent Medicine, 161, 546-552. Sourander, A., Jensen, P., Ronning, J. A., Niemela, S., Helenius, H., Sillanmaki, L., . . . Moilanen, I. (2007). What is the early adulthood outcome of boys who bully or are bullied in childhood? The Finnish “from a boy to a man” study. Pediatrics, 120, 397-404. Sourander, A., Ronning, J. A., Klomek, A. B., Gyllenberg, D., Kumpulainen, K., Niemela, S., . . . Almqvist, F. (2009). Childhood bullying behavior and later psychiatric hospital and psychopharmacologic treatment. Archives of General Psychiatry, 66, 1005-1012. Spano, R., Freilich, J. D., & Bolland, J. (2008). Gang membership, gun carrying, and employment: Applying routine activities theory to explain violent victimization among inner city, minority youth living in extreme poverty*. Justice Quarterly, 25, 381-410. Stein, J. A., Dukes, R. L., & Warren, J. I. (2007). Adolescent male bullies, victims, and bullyvictims: A comparison of psychosocial and behavioral characteristics. Journal of Pediatric Psychology, 32, 273-282. Steinhauer, J. (2013, February). Congress set to consider tighter rules on firearms. The New York Times. Retrieved from http://www.nytimes.com/2013/02/24/us/politics/congress-toconsider-tighter-rules-on-guns.html Sullivan, T. N., Farrell, A. D., & Kliewer, W. (2006). Peer victimization in early adolescence: Association between physical and relational victimization and drug use, aggression, and delinquent behaviors among urban middle school students. Development and Psychopathology, 18, 119-137.

Downloaded from ijo.sagepub.com at University of Manitoba Libraries on June 12, 2015

26

International Journal of Offender Therapy and Comparative Criminology 

Truman, J. (2011). Criminal victimization, 2010 (Bureau of Justice Statistics Bulletin). Washington, DC: Bureau of Justice Statistics. Turner, M. G., Exum, M. L., Brame, R., & Holt, T. J. (2013). Bullying victimization and adolescent mental health: General and typological effects across sex. Journal of Criminal Justice, 41, 53-59. Unnever, J. D., & Cornell, D. G. (2004). Middle school victims of bullying: Who reports being bullied? Aggressive Behavior, 30, 373-388. U.S. Department of Justice, Federal Bureau of Investigation. (2011). Crime in the United States, 2010. Retrieved from http://www.fbi.gov/about-us/cjis/ucr/crime-in-the-u.s/2010/crimein-the-u.s.-2010/tables/10tbl19.xls van der Wal, M. F., de Wit, C. A., & Hirasing, R. A. (2003). Psychosocial health among young victims and offenders of direct and indirect bullying. Pediatrics, 111, 1312-1317. Vaughn, M. G., Fu, Q., Beaver, K. M., DeLisi, M., Perron, B. E., & Howard, M. O. (2011). Effects of childhood adversity on bullying and cruelty to animals in the United States: Findings from a national sample. Journal of Interpersonal Violence, 26, 3509-3525. Vaughn, M. G., Fu, Q., Bender, K., DeLisi, M., Beaver, K. M., Perron, B. E., & Howard, M. O. (2010). Psychiatric correlates of bullying in the United States: Findings from a national sample. Psychiatric Quarterly, 81, 183-195. Veenstra, R., Lindenberg, S., Oldehinkel, A. J., DeWinter, A. F., Verhulst, F. C., & Ormel, J. (2005). Bullying and victimization in elementary schools: A comparison of bullies, victims, bully/victims, and uninvolved preadolescents. Developmental Psychology, 41, 672-682. Vossekuil, B., Reddy, M., Fein, R., Borum, R., & Modzeleski, W. (2000). U.S. secret service safe school initiative: An interim report on the prevention of targeted violence in schools. Washington, DC: U.S. Secret Service National Threat Assessment Center and U.S. Department of Education. Whitehead, J. T., & Langworthy, R. H. (1989). Gun ownership and willingness to shoot: A clarification of current controversies. Justice Quarterly, 6, 263-282. Wilcox, P., & Clayton, R. R. (2001). A multilevel analysis of school-based weapon possession. Justice Quarterly, 18(3), 509-541. Williams, J. S., & McGrath, J. H. (1976). Why people own guns. Journal of Communication, 26(4), 22-30. Wolke, D., Woods, S., Bloomfield, L., & Karstadt, L. (2000). The association between direct and relational bullying and behaviour problems among primary school children. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 41, 989-1002. Wong, J. S., & Schonlau, M. (2013). Does bully victimization predict future delinquency? A propensity score matching approach. Criminal Justice and Behavior, 40, 1184-1208. Yoshikawa, H. (1995). Long-term effects on early childhood programs on social outcomes and delinquency. The Future of Children, 5, 51-75.

Downloaded from ijo.sagepub.com at University of Manitoba Libraries on June 12, 2015

On the Association Between Repeat Bully Victimizations and Carrying a Firearm: Evidence in a National Sample.

Bullying is a significant public concern. The purpose of the present study is to investigate whether being repeatedly victimized by a bully during chi...
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