The trial
How was the trial set up?
Study design
The MapSan trial followed a non-randomised controlled before-and-after study design to evaluate the health impacts of sanitation improvements under the WSUP intervention.
The key goal was to compare health outcomes, such as enteric infections, between children in households receiving the new sanitation facilities and those in households not receiving them.
Baseline data was collected from both groups before the intervention, and follow-up data was gathered after the sanitation upgrades were completed. Follow-up data were collected at three time points: 12 months, 24 months, and 60 months after the intervention.
The non-randomised controlled before-and-after study design allowed researchers to adjust for baseline differences between the groups and account for temporal trends, assuming that confounding variables remained stable over time. By comparing post-intervention outcomes and controlling for household differences, the study was able to estimate the true effect of the sanitation improvements on children’s health.
Study setting
In 2012, approximately 56% of Mozambique’s urban population—roughly 4.5 million people—lacked access to basic sanitation facilities. With rapid urban growth on the horizon, access to safe sanitation remains a critical challenge, particularly in informal settlements.
In Maputo, only 26% of faecal waste is safely managed, while 89% of households rely on onsite waste disposal, and just 10% are connected to sewerage systems. Shared sanitation is common in the poorest communities, and the absence of proper facilities has contributed to frequent cholera outbreaks, widespread enteric infections, and high child mortality rates.
Study location
The MapSan trial was conducted across 11 neighbourhoods in the Nhalamankulu district and 5 neighbourhoods in the KaMaxaquene district of Maputo, Mozambique.
These densely populated, low-income areas are characterised by clusters of households that form self-defined compounds, often enclosed by boundaries and sharing outdoor living spaces and sanitation facilities.
