Effects of inter-group violence on children's and adolescents' morality

This paper systematically reviews the empirical literature on the morality of children and adolescents exposed to inter-group violence and examine whether there is sufficient evidence to claim that exposure to this form of violence exerts an effect and in what direction. The literature review was guided by the PRISMA standards for systematic reviews to search APA PsycNET, PubMed, Web of Science and Google Scholar. Twenty-three empirical articles from 11 countries around the world were retrieved and analyzed for sociodemographic characteristics of the population, characteristics of the conflict and violence, research design, moral outcomes evaluated and effects reported for each, and main findings of the study. Opinion articles, reviews, unpublished papers, dissertations and qualitative study were excluded. Among the findings, most studies found an increase on aggressive behavior, hostility, violence, distribution of resources, and retaliation. While there are mixed results for empathy and pro-sociality. Most studies measured aggressive behavior or pro-social behavior and relied on self-reports - few used behavioral tasks. Also, 60% of the studies were conducted in an ongoing conflict and only 1 study measured long-term effects (10 years after the conflict). Overall, most studies suggest that there is an effect of inter-group violence exposure during childhood and adolescence on moralityand that it is usually negative. However, the few results showing positive outcomes, no effects, and mediators and moderators, also point towards the conclusion that whether the violence of inter-group conflicts exerts an effect and in what direction, depends on other variables. Avenues for future research are delineated.