It is not known whether protective factors in the family, such as family risk factors, lose influence with adolescence. Parental support and encouragement remains important, but even parents who had a good relationship with their children before puberty can only indirectly influence their adolescents` behaviour – for example, through the choice of friends (Elliott et al., 1989). However, this indirect influence is not negligible; Association with peers who reject violence may inhibit later violence in youth (Hawkins et al., 1998c), and positive peer evaluation by parents reduces the risk of crime (Smith et al., 1995). There is growing evidence that factors can increase the risk that young people will be involved in violence – either as victims or perpetrators. These risk factors can be cumulative, with the presence of multiple risk factors increasing the overall risk. Bullying: Unwanted and aggressive behaviour that involves a real or perceived power imbalance. This behaviour is often repeated over time and can have lasting effects on victims. Bullying takes many forms, including verbal, social, online and physical bullying. The effects of children`s exposure to violence on television and film have been extensively studied with respect to aggression, but there is relatively little research on the effects on more severe forms of violent behaviour (see Appendix 4-B for a detailed discussion). Experimental studies have shown that exposure to media violence has a small medium effect (0.13) on severe forms of violence (Paik & Comstock, 1994); The mean effect size in cross-sectional studies was very small (0.06).
Two frequently cited longitudinal studies examined the effects of childhood exposure to television violence on violent behaviour during adolescence or early adulthood. One, in which participants reported hitting, hitting or choking someone as young adults, found a significant predictive effect for women (0.22), but no significant effect for men (Huesmann et al., (submitted)). The other study, in which male adolescents reported involvement in knife fights, car thefts, robberies, gang fights or similar delinquent behaviour, found a statistically significant predictive effect in only one in nine tests (Milavsky et al., 1982). Exposure to violence appears to have a weak predictive effect on relatively immediate violence in experimental studies, but there is little consistent evidence of a long-term predictive effect. This chapter does not mention a number of characteristics and conditions that are often considered risk factors. In addition, some of the identified risk factors may have smaller effect sizes than expected. There are two reasons for this. First, this report builds on longitudinal studies that identify risk factors and their effect sizes based on their ability to predict future behavior. Much of this research involves identifying risks of aggression, externalizing behavior, or antisocial behavior, not risks of violence. Although there is significant overlap between risk factors for aggression and violence, there are important differences, particularly in terms of effect size (Hann & Borek, in press). Violence on television, for example, has a very large impact on aggressive behaviour, but only a small effect on violence.
Second, some studies that have been frequently cited in the media include cross-sectional and retrospective research designs that fail to identify the factors that predict future violence. Not surprisingly, several risk factors for violence are becoming more important in adolescence. Family factors lose predictive value relative to peer-based risk factors, such as weak social connections with conventional peers, antisocial or delinquent friends, and gang membership (Table 4-1). Even participation in general crimes, which was most effective in childhood, has only a moderate effect in adolescence. Through the CrimeSolutions website, NIJ offers reviews of programs and practices designed to prevent violence and provide services to those affected by crime. The CrimeSolutions website contains information on a variety of topics, including school crime, youth gangs and the victimization of violence involving youth. Although bullying is sometimes seen as “part of growth” or “children as children”, bullying in schools is a serious problem. Imagine that the child is hacked every day, whether physically, socially or through cyberbullying.
Think of Rebecca Sedwick, the 12-year-old girl who committed suicide in Florida after being bullied by two young girls for a year. For Rebecca, the bullying was so severe and troubling that she committed suicide. We can protect adolescents and support their growth into healthy adults. Certain factors can increase or decrease the risk that youth will experience or commit violence. To prevent violence involving youth, we need to understand and address the factors that put people at risk of violence or protect them from violence. Scientific theory and research take two different approaches to the evolution of violence involving youth – one that focuses on the occurrence of violent behaviour and its frequency, pattern and continuity throughout life, and the other that focuses on the emergence of risk factors at different stages of the life course. Chapter 3 describes two developmental trajectories for the onset of violent behaviour – one in which violence begins in childhood (before puberty) and continues until puberty, and the other in which violence begins in adolescence. A significant number of laboratory and field experiments over the past half-century have determined whether children exposed to violent behaviour in film or television behave more aggressively immediately afterwards (see reviews of Bushman and Huesmann, 2000; Comstock and Scharrer, 1999; Geen, 1990; Geen and Thomas, 1986; Huesmann et al., 1997).
Many studies have also examined the immediate effects of media violence on aggressive thoughts or emotions (Rule & Ferguson, 1986), which have been shown to increase the risk of aggressive behaviour (Dodge & Frame, 1982; Huesmann and Guerra, 1997). In theory, the effects of exposure to violence in the media extend to Internet media. To date, however, no studies have been published on the effects of web-based media violence on youth aggression and violence. Youth violence is associated with negative health and wellness outcomes and has a disproportionate impact on communities of colour. Violence increases the risk of behavioural and mental health problems. These can include future violence and victimization, smoking, drug use, obesity, high-risk sexual behaviours, depression, academic difficulties, dropping out of school, and suicide. Youth intimate partner violence: This can include physical abuse, sexual abuse, stalking, or psychological harm caused by a current or former partner or spouse. This type of violence can occur in heterosexual or same-sex couples and does not require sexual intimacy. Although the experimental methods used in these studies allow researchers to verify causality more easily than other research methods, as noted by Comstock and Paik (1991), the results do not necessarily apply to all real-world environments. Because experiments focus narrowly on testing specific causal hypotheses, they do not examine the effects of all the factors that might be present in more realistic situations. This means that some real-world influences could actually reduce or even eliminate the aggressive reactions seen in experiments. For example, while television, film, and other media contain a variety of antisocial and other messages, most laboratory studies have so far exposed participants to predominantly violent materials.
In addition, participants may react differently in the laboratory if they realize that their expressions of aggression will not be punished (Gunter, 1983). Any summary of these experimental results should also acknowledge the argument of some critics (such as Freedman, 1992) that many study participants give the answers they believe the researcher wants. Despite these limitations, laboratory experiments are important because they allow researchers to isolate the unique effect of exposure to violence on subsequent behavior. This chapter describes what is known about individual, family, school, peer group and community risks and protective factors that affect childhood and adolescence.