Spillover effects of water, sanitation, and hygiene interventions on child health

描述(由申请人提供)：大量证据表明，水、环境卫生和个人卫生(WASH)干预措施可以有效地减少腹泻病和其他传染病。虽然许多研究已经测量了对接受洗涤干预的儿童的影响，但还没有研究测量它们对与干预接受者相邻的非接受者的影响(溢出效应)。了解溢出效应很重要，因为一旦存在，干预措施的估计效果和成本效益将向下倾斜。尽管有丰富的、基于模型的文献描述了传染病干预措施的溢出效应，但很少有研究从经验上衡量溢出效应。我们提出了一项随机研究，以量化洗涤干预措施的溢出效应。我们的结果将为干预措施的优先顺序提供信息，并指导公共资金的分配。具体目的：我们建议在一项现有的、大型的、设计严谨的试验中衡量水、卫生设施和卫生干预措施的溢出效应：洗涤益处试验。这项试验由比尔和梅琳达·盖茨基金会资助，旨在衡量水、卫生和个人卫生干预措施对儿童健康和发育的单独和综合影响。这是一项在孟加拉国农村地区进行的整群随机对照试验，使用SI治疗臂和双倍大小的对照臂。洗涤福利是设计溢出效应研究的理想平台，因为它设计严谨，规模大(N=5760名新生儿)，而且它评估的个别干预措施的范围很广。我们假设，与生活在对照化合物附近(没有干预)的儿童相比，生活在接受卫生、洗手和水处理综合干预的化合物附近的儿童将有：1)较低的腹泻患病率，2)较低的土壤传播蠕虫感染患病率和强度，以及3)较低的呼吸道疾病患病率。方法：我们将从现有的 联合干预(卫生+洗手+水)和对照手臂的洗涤有益试验。对于每个洗涤福利家庭，我们将找到距离最近的家庭，其0-59个月的孩子没有参加洗涤福利，并收集该家庭的数据。我们的主要结果是照顾者报告的0-59个月儿童的7天腹泻和呼吸道疾病，以及0-59个月儿童(与WASH福利队列相同的年龄)的土壤传播蠕虫感染。我们的研究结果将证明WASH干预措施是否存在溢出效应。创新：这将是第一个通过实验设计对溢出效应进行经验性评估的研究之一，也将是第一个针对洗涤干预措施这样做的研究。我们的创新和跨学科设计以及我们的发现将有助于多个学科(例如经济学、政治学)的方法论。

DESCRIPTION (provided by applicant): A substantial body of evidence suggests that water, sanitation, and hygiene (WASH) interventions can effectively reduce diarrheal illness and other infectious diseases. While numerous studies have measured effects on children receiving WASH interventions, no studies have measured their effects ("spillovers") on non-recipients who live adjacent to intervention recipients. Spillovers are important to understand because, when present, the estimated effects and cost effectiveness of interventions will be biased downwards. Although a rich, model-based literature describes spillovers of infectious disease interventions, few studies have measured spillovers empirically. We propose a randomized study to quantitate spillovers from WASH interventions. Our results will inform prioritization of interventions and guide allocation of public funds. Specific aim: We propose to measure spillovers of water, sanitation, and hygiene interventions in an existing, large, rigorously designed trial: the WASH Benefits trial. Funded by the Bill & Melinda Gates Foundation, this trial aims to measure the individual and combined effects of water, sanitation, and hygiene interventions on child health and development. It is a cluster-randomized, controlled trial with si treatment arms and a double- sized control arm carried out in rural Bangladesh. WASH Benefits is the ideal platform upon which to design a study of spillovers because of its rigorous design, it large size (N=5,760 newborns), and the range of individual interventions it evaluates. We hypothesize that children who live in close proximity to compounds that receive a combined sanitation, hand washing, and water treatment intervention--compared to children who live in close proximity to control compounds (no intervention)--will have: 1) lower prevalence of diarrhea, 2) lower prevalence and intensity of infection of soil transmitted helminths, and 3) lower prevalence of respiratory illness. Methods: We will collect additional data from the existing combined intervention (sanitation+handwashing +water) and control arms of the WASH Benefits trial. For each WASH Benefits household, we will locate the nearest household with children 0-59 months of age that are not enrolled in WASH Benefits and collect data in that household. Our primary outcomes are caregiver-reported 7-day diarrhea and respiratory illness among children 0-59 months as well as soil transmitted helminth infection among children 0-59 months (the same age as the WASH Benefits cohort). Our findings will document either the presence or absence of spillovers of WASH interventions. Innovation: This will be among the first studies to empirically measure spillover effects with an experimental design, and it will be the first study t do so for WASH interventions. Our innovative and interdisciplinary design along with our findings will contribute to methodology in multiple disciplines (e.g. economics, political science)