Neighborhood Safety and Children's Physical Activity, Inactivity and BMI

描述(由申请者提供)：这项研究将调查客观和感知的社区安全措施如何影响幼儿的身体活动、久坐行为和身体质量指数(BMI)，使用基于具有全国代表性的幼儿园儿童样本的纵向模型。本研究有三个具体目的：1.检验社区安全感知和客观测量之间的相关性。2.评估面板数据模型，以检验社区安全感知和客观指标的变化是否会影响儿童的身体活动、久坐行为和BMI。3.检查社区安全、体力活动、久坐行为和BMI的感知和客观措施的影响是否因儿童的社会经济特征而异。我们将使用幼儿纵向研究-幼儿园班级(ECLS-K)的数据，这是一个具有全国代表性的幼儿园样本，包括一年级、三年级、五年级和八年级的跟踪数据。在ECLS-K中，体力活动、不活动、BMI和社区安全感知指标(家长、学校管理人员和面试者报告)分多个阶段提供。通过将ECLS-K的每一年与来自统一犯罪报告的县级犯罪数据和来自各个警察部门的便利样本的普查区级犯罪数据联系起来，将构建社区安全的客观衡量标准。我们的分析方法依赖于儿童固定效应模型，该模型通过利用因变量的变化来确定社区安全的影响，并随着时间的推移对同一儿童的社区安全进行识别。结果将按关键的社会经济特征进行分类，以了解它们与社区安全的相互作用。此外，从多个角度和不同的地理精度水平对社区安全的感知和客观测量结果进行比较，将有助于理清社会环境这一整体方面的重要性。 公共卫生相关性：这项研究可以为解决社区安全和幼儿体育活动行为的政策干预提供信息，以及这些干预措施可能如何受到社会经济特征的影响。这项研究还通过利用感知和客观的安全措施的丰富数据集，为父母的决策提供了更多的洞察力。与以学校为基础的体育活动干预类似，社区安全计划有能力影响大量儿童，使他们成为更广泛的公共卫生战略的潜在重要组成部分。

DESCRIPTION (provided by applicant): This study will examine how objective and perceived measures of neighborhood safety influence young children's physical activity, sedentary behavior, and body mass index (BMI) using longitudinal models estimated on a nationally representative sample of kindergartners. Our study has three specific aims: 1. Examine the correlation between perceived and objective measures of neighborhood safety. 2. Estimate panel data models to examine whether changes in perceived and objective measures of neighborhood safety influence children's physical activity, sedentary behavior, and BMI. 3. Examine whether the influence of perceived and objective measures of neighborhood safety physical activity, sedentary behavior, and BMI vary by children's socio-economic characteristics. We will use data from the Early Childhood Longitudinal Study - Kindergarten Class (ECLS-K), a nationally representative sample of kindergartners with follow-up data in the first, third, fifth and eighth grades. Physical activity, inactivity, BMI and perceived measures of neighborhood safety (parent, school administrator, and interviewer reports) are available in multiple waves in the ECLS-K. Objective measures of neighborhood safety will be constructed by linking each year of the ECLS-K to county level crime data from the Uniform Crime Reports and census tract level crime data from a convenience sample of individual police departments. Our analytical approach relies on child fixed effects models that indentify the effects of neighborhood safety by leveraging changes in the dependent variables and neighborhood safety over time for the same child. Results will be disaggregated by key socioeconomic characteristics in order to understand their interaction with neighborhood safety. In addition, comparison of results using perceived and objective measures of neighborhood safety from multiple perspectives and various levels of geographic precision will be useful in disentangling the importance of this integral aspect of the social environment. Public Health Relevance: This study can inform policy interventions that address neighborhood safety and the physical activity behaviors of young children and how such interventions may be influenced by socio-economic characteristics. The study also provides greater insight on parental decision-making by exploiting a rich dataset of perceived and objective safety measures. Similar to school-based physical activity interventions, neighborhood safety programs have the ability to affect large numbers of children making them a potentially important part of a broader public health strategy.