Do active communities support activity or support active people?

描述（由申请人提供）： 现有的研究表明，关于建筑环境和身体活动之间的关联有希望的结果。然而，很少有人知道如何建成的环境功能是相互关联的，随着时间的推移，和主要的文献是横截面的，因此容易受到住宅选择的偏见，由于缺乏控制的基础上，他们的活动相关的设施的个人选择的环境。目标包括（1）描述关键生命阶段的建筑环境特征模式，以及（2）使用几种方法来控制和量化由于以下原因导致的住宅选择偏差，以估计建筑环境对身体活动的纵向影响：（2a）观察到的特征，（2b）时不变未观察到的特征，以及（2c）时不变未观察到的特征。我们将使用来自一个独特的大规模地理信息系统（GIS）的数据，该系统将两个大的不同种族样本中的社区和个人层面的数据在空间和时间上联系起来。国家青少年健康纵向研究（Add Health）是一项从青春期到青年期的前瞻性队列研究，年轻人冠状动脉风险发展（CARDIA）是一项从青年期开始的前瞻性队列研究，提供了广泛的健康和行为数据。社区一级的各种因素包括土地使用、街道连通性、娱乐设施、经济、气候、犯罪数据等。分析将包括：（1）使用描述性方法和验证性因素分析，我们将描述建筑环境特征的模式，以及这种模式从青少年到青年和中年的不同。基于这些发现，我们将构建建筑环境汇总变量，用于估计建筑环境对后续目标中身体活动的影响。(2)通过使用几种控制住宅选择偏差的方法比较建筑环境对身体活动的纵向影响的估计，我们将量化由于不同类型的因素引起的住宅选择偏差：（2a）观察到的特征：比较随机效应模型（原始估计）与倾向评分加权（观测特性的控制），（2b）时不变的观测和未观测特性：比较2a估计值与固定效应模型，以及（2c）时不变和变化，观察到的和未观察到的特征：比较2a-b估计值与工具变量估计值。这项研究将提高对建筑环境对身体活动的影响做出因果结论的能力。调查结果将改善有关“促进物理环境的建筑环境”的科学知识基础。通过鼓励健康的行为，CDC的“健康的人在健康的地方”健康影响目标的一个目标。它还通过调查在几个关键的生命阶段促进健康的环境，为“生命每个阶段的健康人”的目标作出贡献。

DESCRIPTION (provided by applicant): Existing research shows promising results regarding the association between the built environment and physical activity. However, little is known about how built environment features are interrelated over time, and the predominant literature is cross-sectional and thus vulnerable to residential selection bias due to lack of control for individual choice of environments on the basis of their activity-related amenities. Objectives include (1) Description of built environmental features patterning across key life stages, and (2) Estimation of the longitudinal effects of the built environment on physical activity using several methods to control for and quantify residential selection bias due to: (2a) observed characteristics, (2b) time invariant unobserved characteristics, and (2c) time invariant unobserved characteristics. We will use data from a unique large scale Geographic Information System (GIS) that links community- and individual-level data in both space and time in two large ethnically diverse samples. The National Longitudinal Study of Adolescent Health (Add Health), a prospective cohort followed from adolescence to young adulthood, and the Coronary Artery Risk Development in young Adults (CARDIA), a prospective cohort followed from young adulthood, provide extensive health and behavioral data. A wide range of community-level factors include land use, street connectivity, recreation facilities, economic, climate, crime data, and others. Analyses will include: (1) Using descriptive methods and confirmatory factor analysis, we will describe patterning of built environment characteristics and how this patterning differs from adolescence to young and middle adulthood. Based on these findings, we will construct built environment summary variables to be used to estimate built environment effects on physical activity in subsequent aims. (2) By comparing estimates of the longitudinal effects of the built environment on physical activity using several methods for controlling for residential selection bias, we will quantify residential selection bias due to different types of factors: (2a) observed characteristics: compare random effects models (na¿ve estimate) vs. propensity score weighting (control for observed characteristics), (2b) time invariant observed and unobserved characteristics: compare 2a estimates versus fixed effects models, and (2c) time invariant and variant, observed and unobserved characteristics: compare 2a-b estimates versus instrumental variables estimates. This study will improve the ability to make causal conclusions regarding the effects of the built environment on physical activity. Findings will improve the scientific knowledge base regarding "built environments that promote physical...health by encouraging healthy behaviors...," one objective of CDC's "Healthy People in Healthy Places" health impact goal. It also contributes to the "Healthy People in Every Stage of Life" goal by investigating health-promoting environments throughout several critical life stages.