Nutrition and Clinical Services Division, icddrb, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
Department of Anthropology, Durham University, Durham, UK.
BMC Public Health. 2020 May 22;20(1):744. doi: 10.1186/s12889-020-08769-4.
Evidence of the impact of community-based nutrition programs is uncommon for two main reasons: the lack of untreated controls, and implementation does not account for the evaluation design. Suchana is a large-scale program to prevent malnutrition in children in Sylhet division, Bangladesh by improving the livelihoods and nutrition knowledge of poor and very poor households. Suchana is being implemented in 157 unions, the smallest administrative unit of government, in two districts of Sylhet. Suchana will deliver a package of interventions to poor people in about 40 randomly selected new unions annually over 4 years, until all are covered. All beneficiaries will receive the normal government nutrition services. For evaluation purposes the last 40 unions will act as a control for the first 40 intervention unions. The remaining unions will receive the program but will not take part in the evaluation. A baseline survey was conducted in both intervention and control unions; it will be repeated after 3 years to estimate the impact on the prevalence of stunted children and other indicators. This stepped wedge design has several advantages for both the implementation and evaluation of services, as well as some disadvantages. The units of delivery are randomized, which controls for other influences on outcomes; the program supports government service delivery systems, so it is replicable and scalable; and the program can be improved over time as lessons are learned. The main disadvantages are the difficulty of estimating the impact of each component of the program, and the geographical distribution of unions, which increases program delivery costs. Stepped implementation allows a cluster randomized trial to be achieved within a large-scale poverty alleviation program and phased-in and scaled-up over a period of time. This paper may encourage evaluators to consider how to estimate attributable impact by using stepped implementation, which allows the counterfactual group eventually to be treated.
基于以下两个主要原因，针对社区营养项目的影响通常缺乏证据：缺乏未经处理的对照组，以及实施情况并未考虑评估设计。Suchana 是孟加拉国锡尔赫特地区一个旨在通过改善贫困和赤贫家庭的生计和营养知识来预防儿童营养不良的大型项目。Suchana 正在锡尔赫特的两个区的 157 个联盟（政府的最小行政单位）中实施。在 4 年的时间里，Suchana 将每年向大约 40 个随机选择的新联盟中的贫困人口提供一揽子干预措施，直到全部覆盖。所有受益人将获得正常的政府营养服务。出于评估目的，最后 40 个联盟将作为前 40 个干预联盟的对照。其余联盟将获得该项目，但不会参与评估。在干预和对照联盟中都进行了基线调查；三年后将再次进行调查，以估计对发育迟缓儿童和其他指标的流行率的影响。这种阶梯式楔形设计对服务的实施和评估都有几个优势，同时也有一些劣势。交付单位是随机的，这控制了对结果的其他影响；该方案支持政府服务提供系统，因此具有可复制性和可扩展性；并且随着经验教训的积累，该方案可以随着时间的推移得到改进。主要缺点是难以估计该方案每个组成部分的影响，以及联盟的地理分布，这增加了方案的交付成本。阶梯式实施允许在大规模扶贫计划内实现集群随机试验，并在一段时间内分阶段实施和扩大规模。本文可能会鼓励评估人员考虑如何通过使用阶梯式实施来估计归因影响，这允许最终对反事实组进行治疗。
