PROJECT 1: Child Policy Fit in Experimental Early Childhood Interventions

项目总结（见说明）： 我们采用的儿童环境适合的角度来推导和测试假设的儿童，家庭和儿童保育计划的特点的组合导致更大的儿童保育治疗效果的认知和社会情感的入学准备结果的儿童。我们首先检验一个补偿性假设，即高质量的儿童保育有利于高危儿童。这是一个实验性测试，使用的数据来自五个评估，采用高质量的儿童保育实验操作-婴儿健康和发展计划（IHDP），早期开端（EHS），国家开端影响研究（NHSIS）和随机学前课程评估研究（PCER）。还使用俄克拉荷马州通用Pre-K程序的回归不连续设计进行了检验。第二组实验测试是使用IHDP、NHSIS、俄克拉荷马州Pre-K和PCER研究的数据，对补偿性假设（技能最低的儿童获益最多）和技能产生技能假设（技能最高的儿童获益最多）的竞争性预测进行的。第三，我们使用来自EHS，NHSIS和PCER的数据来检验保护性假设，即某些个人和家庭因素可以保护高危儿童免受低质量护理的负面影响。我们使用这些相同的数据来检验累积劣势假设，即低质量的项目对具有大量风险因素的儿童最有害。最后，我们测试的差异易感性假说，即儿童与困难的气质是在一次伤害最低质量的照顾，但帮助最高质量的照顾。此外，我们还将对两个随机数据库进行分析，即NHSIS和PCER，这两个数据库提供了关于项目特征变化的非常详细的信息，以确定哪些特征导致了人群亚组所经历的差异效应。我们将使用一个工具变量策略，该策略采用由于实验治疗而导致的程序特征的变化，以提供这些特征对儿童结局的影响的无偏估计。我们期望为新一代学前儿童保育计划提出建议，旨在确定全球和特定内容质量以及质量的其他详细方面的影响，使计划功能更好地适应特定儿童的需求和背景。在所有的情况下，从NHSIS的数据被用来测试这些假设，我们将协调我们的结果与项目III的使用分布方法的NHSIS。

PROJECT SUMMARY (See instructions): We employ the child-environment fit perspective to derive and test hypotheses about which combinations of child, family, and child care program characteristics lead to larger child care treatment effects on cognitive and socio-emotional school readiness outcomes for children. We first test a compensatory hypothesis in which high-quality child care benefits at-risk children. This is an experimental test using data from five evaluations that employ an experimental manipulation of high-quality child care - t he Infant Health and Development Program (IHDP), Early Head Start (EHS), the National Head Start impact Study (NHSIS), and the randomized Preschool Curriculum Evaluation Research Study (PCER). Tests are also performed using the regression-discontinuity design of the Oklahoma Universal Pre-K program. A second set of experimental tests are of competing predictions from compensatory (least skilled children profit the most) and skill begets skill (the most skilled children profit the most) hypotheses using data from the IHDP, NHSIS, Oklahoma Pre-K, and PCER studies. Third, we use data from EHS, NHSIS, and PCER to test the protective hypothesis that certain personal and family factors protect at-risk children from the negative effects of low-quality care. We use these same data to test the cumulative disadvantage hypothesis that poor-quality programs are most detrimental for children with a high number of risk factors. Finally, we test the differential susceptibility hypothesis that children with difficult temperaments are at once hurt the most by low-quality care but helped the most by high-quality care. In addition, we will undertake analyses of two randomized databases ¿ the NHSIS and PCER -that provide very detailed information on variation in program characteristics, in order to determine which characteristics account for differential effects experienced by population subgroups. We will use an instrumental variables strategy that employs the variation in program characteristics due to the experimental treatment to provide unbiased estimates of the effects of these characteristics on child outcomes. We expect to produce recommendations for a new generation of preschool child care programs aimed at identifying effects of global and content-specific quality as well as other detailed aspects of quality, enabling program features to be better aligned to particular children's needs and background. In all cases in which data from the NHSIS are used to test these hypotheses, we will reconcile our results with those from Project Ill's use of distributional methods on the NHSIS.