School Environment as a Mechanism to Reduce Youth Violence and Victimization

青少年暴力给个人和社会带来巨大的代价。青少年暴力是10至24岁人群死亡的第二大原因。每年有720 000多名青少年因暴力相关伤害在急诊室接受治疗（疾病预防控制中心，2008年a）。这些伤害在少数民族青年中尤为严重。改善学校环境可以作为一种有效的预防性干预措施，因为它们是青年的环境支柱，是与青年暴力行为普遍存在有关的地方环境的一系列结构性特征的一部分。鉴于大多数人在上学期间开始暴力行为，学校在考虑如何促进个人内部的亲社会变化，从而减少暴力行为的发生方面提供了一个天然的联系。在家庭之外，学校是最重要的社会控制机构。即使考虑到当地社区和家庭的相关因素，在管理不善和资源匮乏的学校上学的青年更有可能遭受暴力。青少年在一天中最容易发生犯罪的时间集中在校园内或周围，这表明学校是产生暴力的自然生态环境。拟议的研究将通过分析学校作为中介保护因素的作用，扩大我们对青少年暴力流行病学的理解。我们认为，改善学校环境是降低青少年暴力和受害总比率的一个重要中介因素。改善学校环境还可以促进社区与青年暴力有关的系统性方面的变化（例如，社会凝聚力、集体效能）。由于缺乏实验证据，我们依靠自然实验来产生学校环境中的外源性变化，并评估其对青少年暴力的影响在多个层面，包括国家，地区和学校。这种方法通常用于估计对学业成绩的因果影响，但尚未广泛应用于青年暴力的结果。我们的方法依赖于州内，区内和校内的变化，通过固定效应回归，并在相关的情况下，工具变量和倾向评分方法来估计对青年暴力的影响。我们还将按种族/民族分解我们的估计。这项研究将是评估旨在改善学校环境的基础广泛的社会政策努力对州、地区和学校各级青年暴力结果的影响的首批努力之一。通过对学区、执法部门和公共卫生部门收集的关于青少年暴力和受害结果的监测数据进行分析，我们可以提供学校对社区青少年暴力影响的流行病学评估。该项目旨在实现“2010年健康人民”的目标，重点领域是预防伤害和暴力。青年暴力给个人和社会带来巨大代价，其危害在少数群体中尤为严重。这项拟议的研究将通过分析学校作为减少这些伤害的中介保护因素的作用，扩大我们对青少年暴力流行病学的理解。该项目旨在实现“健康人民2010”的目标，重点领域是预防伤害和暴力，以及国家卫生研究院呼吁对健康方面的种族/族裔差异进行研究。

Description (Provided by Applicant): Youth violence imposes enormous costs on individuals and society. Youth violence is the second leading cause of death among individuals ages 10 to 24. Each year, over 720,000 youth are treated in emergency rooms for violence-related injuries (CDC, 2008a). These harms are particularly acute among minority youth. Improving school environments may serve as an effective preventative intervention because they are environmental anchors for youth and are part of the larger set of structural features of local environments linked to the prevalence of youth violence. Given that most individuals initiate violent behaviors during school years, schools provide a natural nexus in considering how to promote pro-social change within individuals and consequently reduce the prevalence of violence. Outside of the family, schools represent the most important institution of social control. Youth attending poorly-managed and resource-deprived schools are more likely to be exposed to violence, even after accounting for local community and family-related attributes. The concentration of youth on/around school grounds during the most crime prone times of the day, suggests that schools are natural ecological environments from which violence can generate. The proposed study will expand our understanding of the epidemiology of youth violence by analyzing the role of the school as a mediating protective factor. We theorize that improving the school environment is an important mediating factor in reducing aggregate rates of youth violence and victimization. Improving school environments can also putatively foster changing systemic aspects of communities linked to youth violence (e.g., disorder, social cohesion, collective efficacy). Given the lack of experimental evidence, we rely on natural experiments to generate exogenous variation in school environments and assess their effects on youth violence at multiple levels including state, districts, and schools. This approach is commonly used to estimate a causal impact on academic achievement, but has not been applied widely to youth violence outcomes. Our methodology relies on within-state, within-district and within- school variation via fixed effects regressions and, where relevant, instrumental variables and propensity score approaches to estimate the effects on youth violence. We will also disaggregate our estimates by race/ethnicity. The study will be among the first efforts to assess the effects of broad-based social policy efforts aimed at improving school environments on youth violence outcomes at state, district, and school levels. Through the analysis of surveillance data on youth violence and victimization outcomes collected by school districts, law enforcement, and public health departments, we can provide an epidemiological assessment of school effects on youth violence in the community. This project addresses the goals of Healthy People 2010 focus areas of Injury and Violence Prevention. Youth violence imposes enormous costs on individuals and society and its harms are particularly acute among minority populations. The proposed study will expand our understanding of the epidemiology of youth violence by analyzing the role of the school as a mediating protective factor in reducing these harms. This project addresses the goals of Healthy People 2010 focus areas of Injury and Violence Prevention and the National Institutes of Health call for research on racial/ethnic disparities in health.