Estimating the Impact of Out-of-Home Placement on Health Risk Behavior in Adolescents Exposed to Maltreatment: An Advanced Causal Inference Approach

摘要 虐待儿童与危害健康的行为有关，这些行为带来了高昂的个人和社会代价， 如药物使用和危险性行为。1 -4将儿童安置在家庭外照料的目的是 减轻这些负面影响。5关于接受家庭外护理的青少年健康风险行为率的调查结果 混合，6-16，虽然研究表明，以前在照顾的年轻人有更高的健康风险水平 17 -20这些喜忧参半的发现可能是由于大多数研究都测试了跨性别的安置效果。 童年对以后健康危险行为的影响。然而，青春期的安置可能是一个转折点， 重定向健康风险行为的轨迹。青春期是一个快速变化的时期，也是一个典型的 这些行为的开始，21和青少年有更多的困难，以适应安置比年轻 22为了检验青少年的安置是否是一个转折点，重要的是要知道， 放置启动轨迹的长期变化、短期（特定时间）变化或两者。设计 除了干预措施外，还需要了解安置效应的潜在机制。然而，在这方面， 由于放置可能发生在不同的时间点，识别其直接和间接影响需要 将家庭外安置、中介因素、混杂因素和结果建模为随时间变化的变量。 重要的是，家庭外安置是一个非随机事件，许多安置前的变量可能 预测安置和随后的健康风险行为。为了应对这种对因果推理的威胁，最近 研究采用了倾向评分法。23 -27然而，这些方法不能适应时间- 不同的变量，排除测试的位置作为一个转折点或测试其特定时间的调解人。 因此，拟议的研究使用了两种现代因果推理方法， 治疗加权（IPTW）和g-估计，以测试放置对健康风险的直接和介导影响 时间上的行为。这些方法可以解释来自观察到的混杂因素的偏倚， 目标1检验自上一波以来， 显示短期，特定时间的物质使用和无保护性行为的开始增加，与那些 谁留在家里。目标2测试青少年安置是否预测成人健康的长期提升 风险行为目的3测试时变介质的安置对成人健康危险行为的影响。 这些目标将在全国范围内对738名受虐待的青少年（基线年龄为11-14岁）进行抽样调查， 四波到成年。培训计划汇集了一个杰出的指导团队， 儿童福利系统研究的多学科培训，因果推理的现代定量方法， 健康危险行为的发展性精神病理学，对干预和政策的影响， 专业发展。这将为申请人提供开展研究生涯的基础 研究安置和儿童福利参与对青少年发展成果的影响。

ABSTRACT Child maltreatment is associated with health risk behaviors carrying high personal and societal costs, such as substance use and sexual risk behavior.1–4 Placement of children into out-of-home care aims to mitigate these negative effects.5 Findings about rates of health risk behavior among youth in out-of-home care are mixed,6–16 although studies show that young adults formerly in care have heightened levels of health risk behavior.17–20 These mixed findings may be due to the fact that most studies test effects of placement across childhood on later health risk behaviors. However, placement during adolescence may be a turning point that redirects trajectories of health risk behavior. Adolescence is a period of rapid change and a typical period for initiation of these behaviors,21 and adolescents have more difficulties adjusting to placement than do younger children.22 To test whether adolescent placement acts as a turning point, it is important to know whether placement initiates long-term changes in trajectories, short-term (time-specific) changes, or both. To design interventions, it is also necessary to understand the mechanisms underlying placement effects. However, because placement may occur at various points across time, identifying its direct and mediated effects requires modeling out-of-home placement, mediators, confounders, and outcomes as time-varying variables. Importantly, out-of-home placement is a nonrandom event, and many pre-placement variables likely predict both placement and subsequent health risk behavior. To deal with this threat to causal inference, recent research has utilized propensity score methods.23–27 However, these methods cannot accommodate time- varying variables, precluding tests of placement as a turning point or tests of its time-specific mediators. Accordingly, the proposed study uses two modern methods for causal inference, inverse probability of treatment weighting (IPTW) and g-estimation, to test direct and mediated effects of placement on health risk behaviors across time. These methods can account for biases from observed confounders and accommodate time-varying variables.28,29 Aim 1 tests whether adolescents with out-of-home placement since the prior wave show short-term, time-specific increases in substance use and initiation of unprotected sex, compared to those who remain in-home. Aim 2 tests whether adolescent placement predicts longer-term elevations in adult health risk behavior. Aim 3 tests time-varying mediators of the effect of placement on adult health risk behavior. These aims will be tested in a national sample of 738 maltreated youth (age 11-14 at baseline) studied across four waves to adulthood. The training plan brings together a distinguished mentoring team to provide multidisciplinary training in child welfare system research, modern quantitative methods for causal inference, developmental psychopathology of health risk behaviors, implications for intervention and policy, and professional development. This will provide the applicant with the foundation to launch a research career studying the effects of placement and child welfare involvement on adolescents' developmental outcomes.