An advanced cookstove intervention to prevent pneumonia in children under 5 years old in Malawi: a cluster randomised controlled trial

马拉维是婴儿和五岁以下儿童死亡率最高的国家之一（2009年分别为每1 000名活产69人和110人），尽管该国在实现降低儿童死亡率的千年发展目标方面取得了进展。肺炎是死亡的主要原因，也是最常见的发病原因之一，每年每1000名5岁以下儿童中约有298人被诊断患有肺炎，病死率为每1000人中2.7至13.2人。暴露于生物质燃料（动物或植物材料）在明火中燃烧时产生的烟雾是肺炎的一个主要可避免的风险因素。在马拉维，至少95%的家庭依赖生物质作为其主要燃料来源，生物质烟雾暴露可能是造成这种疾病的重大负担的原因。目前已有减少接触烟雾的有效战略（例如通风、改良炉灶、清洁燃料、行为改变），但由于各种主要与贫穷有关的因素，大多数人无法实现这些战略。全球清洁炉灶联盟于2010年启动，旨在通过公私伙伴关系解决这一能源贫穷问题。该联盟的一个核心目标是到2020年使1亿个家庭采用清洁和高效的炉灶和燃料。然而，评估这种方法的潜在好处的证据非常有限。我们在撒哈拉以南非洲开展了筹备和试点工作，以确定目前可用的先进炉灶中哪一种最适合在马拉维进行试验，以提高燃烧效率、减少排放和烹饪当地菜肴的能力。我们已作出相当大的努力，让当地社区参与制定这项建议。我们现在能够研究一种有效的和当地可接受的先进炉灶，在试验中大大减少烟雾排放，以解决三个主要研究问题：1）先进炉灶干预，大大减少生物质烟雾暴露相对于明火，可以预防马拉维5岁以下儿童的肺炎？2)从家庭、医疗保健系统和社会角度来看，干预措施的可负担性和成本效益如何？3)从试验参与者和非参与者那里可以学到什么关于采取干预措施的知识，这些干预措施可以为将来有效实施试验结果提供信息？需要家庭采用先进炉灶技术对健康和经济影响的高质量临床试验证据，以便为地方、区域和国际各级商业、卫生、发展和社区部门的政策制定者提供信息。这项试验的结果将与马拉维当地决策者有关，他们将获得新的功效、经济和质量数据，以指导关于为改善儿童健康的先进炉灶方案供资的决定;与撒哈拉以南非洲制造和分销先进炉灶解决方案的区域商业、非政府和政府组织有关;并向国际（如世界卫生组织（WHO））决策者和政策制定者提供新的证据，说明先进炉灶干预措施对世界上生物质燃料使用普遍的地区的健康和经济影响。我们已经建立了地方（如社区领袖），区域（如商业和非政府组织和马拉维卫生部）和国际（如世卫组织和全球清洁炉灶联盟）的联系，这将使我们能够在各级有效地向广泛的利益相关者，政策制定者和决策者传播试验结果。

Malawi has one of the highest rates of death among infants and the under fives (69 and 110 per 1000 live births respectively in 2009) despite having made progress towards meeting the Millennium Development Goal of reducing child mortality. Pneumonia is the leading cause of death and one of the commonest causes of morbidity with around 298 per 1000 children under the age of 5 diagnosed with pneumonia every year and a case fatality rate between 2.7 and 13.2 per 1000. Exposure to smoke produced when biomass fuels (animal or plant material) are burned in open fires is a major avoidable risk factor for pneumonia. In Malawi, where at least 95% of households depend on biomass as their main source of fuel, biomass smoke exposure is likely to be responsible for a substantial burden of this disease. Effective strategies for reducing smoke exposure exist (e.g. ventilation, improved stoves, cleaner fuels, behaviour modification) but are out of reach for the majority due to a wide range of largely poverty-related factors. The Global Alliance for Clean Cookstoves was launched in 2010 to tackle this energy poverty issue through public private partnerships. A central aim of the alliance is for 100 million homes to adopt clean and efficient stoves and fuels by 2020. However, there is very limited evidence to assess the potential benefits of such an approach. We have conducted preparatory and pilot work in sub Saharan Africa to determine which of the currently available advanced cookstoves would be most suitable for use in a trial in Malawi in terms of improvements in combustion efficiency, reduced emissions and ability to cook local dishes. We have gone to considerable lengths to involve local communities in the development of this proposal. We are now in a position to be able to study an efficient and locally acceptable advanced cookstove that substantially reduces smoke emissions in a trial to address three principal research questions: 1) Can an advanced cookstove intervention that substantially reduces biomass smoke exposure relative to an open fire prevent pneumonia in children under 5 years old in Malawi?2) How affordable and cost effective is the intervention from household, healthcare system and societal perspectives?3) What can be learned from trial participants and non-participants about adoption of the intervention that could inform effective implementation of the trial findings in the future?High quality clinical trial evidence about the health and economic impacts seen when households adopt advanced cookstove technologies is needed to inform policy and decision makers across commercial, health, development and community sectors at local, regional and international levels. The results of this trial will be relevant to local policy makers in Malawi who will have new efficacy, economic and qualitative data to guide decisions about funding advanced cookstove programmes for improving child health; to regional commercial, non-governmental and governmental organisations in sub Saharan Africa manufacturing and distributing advanced cookstove solutions; and to international (e.g. World Health Organisation (WHO)) decision and policy makers by contributing new evidence about the health and economic impacts of an advanced cookstove intervention of broadly generalisable relevance to areas of the world where biomass fuel use is common. We have established local (e.g. community leaders), regional (e.g. commercial and non-governmental organisations and Malawi Ministry of Health) and international (e.g. WHO and Global Alliance for Clean Cookstoves) links that will allow us to disseminate the findings of the trial effectively at all levels to a wide range of stakeholders, policy and decision makers.