Seungman Cha1,2, JaeEun Lee1*, DongSik Seo3, Byoung Mann Park3, Paul Mansiangi4, Kabore Bernard5, Guy Jerome Nkay Mulakub-Yazho6 and Honore Minka Famasulu6


Background: The lack of safe water and sanitation contributes to the rampancy of diarrhea in many developing countries.
Methods: This study describes the design of a cluster-randomized trial in Idiofa, the Democratic Republic of the Congo, seeking evidence of the impact of improved sanitation on diarrhea for children under four. Of the 276 quartiers, 18 quartiers were randomly allocated to the intervention or control arm. Seven hundred and-twenty households were sampled and the youngest under-four child in each household was registered for this study. The primary endpoint of the study is diarrheal incidence, prevalence and duration in children under five.
Discussion: Material subsidies will be provided only to the households who complete pit digging plus superstructure and roof construction, regardless of their income level. This study employs a Sanitation Calendar so that the mother of each household can record the diarrheal episodes of her under-four child on a daily basis. The diary enables examination of the effect of the sanitation intervention on diarrhea duration and also resolves the limitation of the small number of clusters in the trial.
In addition, the project will be monitored through the ‘Sanitation Map’, on which all households in the study area, including both the control and intervention arms, are registered. To avoid information bias or courtesy bias, photos will be taken of the latrine during the household visit, and a supervisor will determine well-equipped latrine uptake based on the photos. This reduces the possibility of recall bias and under- or over-estimation of diarrhea, which was the main limitation of previous studies.
Trial registration: The study was approved by the Institutional Review Board of the School of Public Health, Kinshasa University (ESP/CE/040/15; April 13, 2015) and registered as an International Standard Randomized Controlled Trial (ISRCTN: 10,419,317) on March 13, 2015.
Keywords: Sanitation, Diarrhea, Well-equipped latrine, Sanitation calendar

Infectious Diseases of Poverty

Cha et al. Infectious Diseases of Poverty (2017) 6:137
DOI 10.1186/s40249-017-0351-x