Antisocial behaviour is a public health concern in many societies and can adversely affect not only individual perpetrators and victims, but the social and economic functioning of communities as a whole. Strategies aimed at preventing antisocial behaviour tend to take a developmental approach though many interventions have been criticised for their narrow focus on individual, rather than societal risk factors. The media is one of several potentially important contributing factors to antisocial behaviour and a large number of studies have been conducted to examine the relationship between television violence and antisocial behaviour. Experimental studies have provided good evidence that exposure to screen violence increases aggressive behaviour in the short-term. Cross-sectional studies indicate that increased exposure to media violence is associated with increased antisocial behaviour, however, the debate about whether television plays a causal role in the development of antisocial behaviour is ongoing. Few longitudinal studies have been carried out in this area, and those that have been completed have produced inconsistent results.
The present study uses data from the Dunedin Multidisciplinary Health and Development Study (DMHDS), to test the hypothesis that watching larger amounts of television during childhood and adolescence is associated with increased antisocial behaviour in early adulthood. The DMHDS is an ongoing longitudinal study of 1,037 Study members born between 1972 and 1973 in Dunedin, New Zealand. Study members have been assessed at birth, then every 2 years until age 15, then again at ages 18, 21 and 26 years. The main exposure measure was the mean weekday television viewing hours between 5 and 15 years old. Primary outcome measures were 1) having any type of conviction; 2) having a violent conviction, and 3) being diagnosed with antisocial personality disorder by age 26, and 4) levels of Negative Emotionality at ages 18 and 26.
More television viewing between the ages of 5 and 15 years old was significantly associated with increased odds of having a criminal conviction and a diagnosis of antisocial personality disorder by age 26, and higher Negative Emotionality scores, after a range of potential confounders was controlled for. Supplementary analyses provided some evidence that children aged 5 to 11 may be particularly susceptible to any effects of television viewing on antisocial behaviour. Given these findings, public health interventions aimed at reducing exposure to television violence would likely reduce antisocial behaviour in a population. Legislative measures concerning television broadcasting have been introduced in the United States, though these approaches have been largely ineffective. An alternative approach could include encouraging health professionals to incorporate advice about media use into child health assessments, and supporting health promoters to develop community-based programmes aimed at reducing television violence exposure. Further research is required on the effectiveness of media literacy as a way of mitigating the effects of exposure to television violence. Given the growth in new media technologies, and the fact that excessive use of media has been implicated in a range of adverse outcomes for young people, more research on the effectiveness of interventions to reduce overall media use is critical.
