Effect of Improved "Injera" Baking Stove Intervention on Household Air Pollution and Childhood Acute Respiratory Infection Prevention: A Cluster Randomized Controlled Trial In Northwest Ethiopia
试验速览
- 阶段
- 不适用
- 入组人数
- 5,500
- 试验地点
- 2
- 主要终点
- Longitudinal proportion of childhood acute respiratory infection as measured by childhood pneumonia status using World Health Organization's Integrated Management of Neonatal and Childhood Illness algorism.
研究概览
简要总结
In Ethiopia, great majorities (95%) of households rely on solid biomass fuels such as wood, muck, crop residues, and charcoal burned in highly polluting stoves to meet the basic household energy needs with its severe health consequences due to emission of toxic indoor air pollutants. Correspondingly, household air pollution (HAP) from biomass fuel use is now estimated to be responsible for nearly 3.5 million premature deaths annually, with the highest disease burdens experienced by countries in sub-Saharan Africa. HAP ranks as the highest environmental risk factors to premature deaths globally and 2nd leading risk factor next to childhood underweight in most of sub-Saharan Africa countries as well as 3rd leading risk factor of disease next to childhood underweight, and suboptimal breastfeeding in Ethiopia.
Usually prevention efforts aimed at reducing HAP and related health burdens have been focused on the use of energy efficient cookstoves. There is, however, rigorous lack of evidence in Ethiopia or in other similar settings whether it is possible to achieve adequate HAP reduction and improve health with locally made energy efficient baking stoves from a public health point of view. Particularly, the popular Ethiopian energy efficient "Injera" baking stove has not been researched through stove trial inquiry. Therefore, research studies are required in Ethiopia on health benefits achieved when households adopt energy efficient baking stoves. In view of that, cluster randomized controlled trial will be employed with experimental study design for one year to test the effectiveness of the Ethiopian improved "Injera" baking stove intervention on reducing HAP and childhood acute respiratory infection (ARI) through comparing equal size groups of children before and after part of households received an improved "Injera" baking stove.
Accordingly, the proposed stove trial aims to address an important research gap by determining whether the Ethiopian improved "Injera" baking biomass stove intervention can adequately reduce HAP exposure to prevent childhood acute respiratory infection. With this objective, the proposed stove trial will test the hypothesis that there is a statistically significant difference in HAP levels and incidence of childhood ARI when using traditional versus improved "Injera" baking stove in Northwest Ethiopia
详细描述
- Study area:
The implementation of the study project has been started among rural and urban communities of Mecha Health & Demographic Surveillance System (MHDSS) Site in Northwest Ethiopia. MHDSS site is a field research center established by Bahir Dar University (BDU) to conduct field researches & support major graduate level research projects principally. The field research center is located at 525 km far away from the capital city of Ethiopia, Addis Ababa, towards Northwest. This field research center has been selected as study area in light of the following particular rationales:
- Relevance of the project to the community in terms of current biomass fuel use, climatic diversity & local acceptability of the improved stove intervention
- Strategic research importance of the locality to achieve the mission's of BDU to be one of the ten premiere research universities in Africa by the year 2025.
- Opportunities to be benefited from the existing field research infrastructures of MHDSS
- Availability of local collaborators with experience of improved stove technology transfer
- Availability of improved baking stove initiatives already operating in the study area
- Good field experience of investigators at the study area
- Study design:
Cluster randomized controlled study will be employed to test the effectiveness of improved "Injera" baking biomass stove intervention in reducing both household air pollution (HAP) & childhood acute respiratory infection (ARI) incidences through comparing children living in households (HHs) with different baking stoves over one year follow-up period. With this study design, HAP & childhood ARI outcomes will be measured before the improved baking stove is installed and again after part of the HHs received an improved baking stove. The overall study procedures will involve the following three major phases:
- Base line data collection using HH interview and air monitoring methods.
- Installing improved "Injera" baking biomass stove in the main cooking area of the intervention HHs to be used as primary baking stove at least for one year.
- Consecutive data collection using the HH interview method every 2 weeks and measure the new amounts of indoor particulate matter in the main cooking area using standard HAP monitoring device every 3 months for one year.
- Sample size:
For the primary outcome, the sample size was calculated by applying the two-sample comparison of proportions formula using STATA with equal participants in both arms considering 21% proportion of childhood ARI, detectable difference of 20%, & two-tailed alpha of 0.05, power of 80%, intra-cluster correlation coefficient (Ƿ) value of 0.01, coefficient of variation of 0.6 for cluster sizes, 55 average number of children within each cluster (m') and over sampling of 10%; the required sample size with cluster randomization becomes about 2750 within 50 clusters per arm. Similarly, for the secondary outcome, the sample size was calculated by considering detectable difference of 60% in mean indoor PM2.5 concentration (µg/m3), correlation coefficient (Ƿ) of 0.5 for indoor PM2.5 measurement variations in biomass using HHs, 2-sided alpha of 0.05, power of 80% and 55 average number of children within each cluster (m'), 0.6 coefficient of variation for cluster sizes and over sampling of 10%; the required sample size becomes about 990 within 18 clusters per arm. Thus, among the HHs included in the primary outcome study, only part of the HHs will be included for the secondary outcome study. 4. Sampling method:
Using cluster sampling technique, clusters/"Gotes" will be selected randomly to represent the total population & then all HHs with under 4 years old child with in the selected clusters will be included. A cluster is defined as the small village, termed as "Gote" for rural or "Ketena" for urban settings in Amharic (both national & local language), used as the smallest unit of enumeration area by Ethiopian national census. According to the update data report of MHDSS at the end of 2017, each cluster/"Gote" includes about 55 average number of children. To set the randomisation list in advance based on eligibility criteria, the sampling frame (list of HHs with children less than 4 years old) is established form the MHDSS update report data. Finally, the selected HHs will be identified for data collection using the specific MHDSS house number & the youngest child equal or less than 4 years old will be recruited for study from each HH. In situations where there are 2 or more under-four children living in the same HH, only the youngest child will be included in the study. 5. Participant recruitment:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- — 至 48 Months（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Households with children up to 4 years old to ensure a minimum of one year longitudinal data collection before the child's 5th birthday.
- •Households who bake "Injera" exclusively with a traditional baking stove
排除标准
- •Households who do not have any enclosed main cooking area (kitchen) structure
- •Children who will be born during the course of the study
研究组 & 干预措施
Improved "Injera" Baking Biomass Stove
2750 eligible households with in 50 randomly selected clusters/"Gotes" are allocated into the improved "Injera" backing stove intervention arm.
干预措施: Improved "Injera" Baking Biomass Stove (Device)
Control arm
Similarly 2750 eligible households with in 50 randomly selected clusters/Gotes will continue to use the traditional "Injera" baking biomass stove and will be used as control arm.
结局指标
主要结局
Longitudinal proportion of childhood acute respiratory infection as measured by childhood pneumonia status using World Health Organization's Integrated Management of Neonatal and Childhood Illness algorism.
时间窗: Change from baseline childhood ARI due to Improved "Injera" Baking Stove Intervention will be assessed at one year.
Childhood acute respiratory infection/pneumonia status will be assessed using standard case recording form by field workers during household visits where the index child mothers/caregivers are asked about ARI signs \& symptoms in the preceding two weeks. Moreover, to overcome some of the limitations of the self-reported health data, physical examination of the ill index child will be conducted by field workers trained in World Health Organization's Integrated Management of Neonatal and Childhood Illness algorism.
次要结局
- Household air pollution as measured by concentration of indoor particulate matter with an aerodynamic diameter of less than 2.5 microns (PM2.5) in µg/m3(Change from baseline HAP (indoor PM2.5 concentration) due to Improved "Injera" Baking Stove Intervention will be assessed at one year.)
研究者
Mesafint Molla
Assistant Professor at School of Public Health, College of Medicine and Health Sciences
Bahir Dar University