The role of mortality estimation in project evaluation: Findings from a household survey in Dembo and Beboro health zones, Chad

INTRODUCTION

In the Mandoul region of Chad, multiple indicators point to an ongoing protracted crisis including high child mortality, food insecurity, and elevated malaria incidence. Since 2018, Médecins Sans Frontières (MSF) has provided seasonal malaria chemoprevention and supported maternal and child health services in Moissala district. In 2023, they conducted a mortality survey to evaluate population health in the supported areas.

METHODS

MSF conducted a stratified two-stage cluster survey in Dembo and Beboro health zones. Geospatial sampling was used to select cluster starting points, with three households interviewed per cluster. A sample size of 4,970 people was targeted in each zone. The questionnaire captured household demographics, births, deaths, and migration over an 8-month recall period.

RESULTS

In Dembo, 311 clusters covered 849 households and 5,504 people. In Beboro, 326 clusters covered 895 households and 4,999 people. Dembo had a high crude mortality rate (CMR) of 0.89 (95%CI: 0.70, 1.08) deaths/10,000 people/day and under-five mortality (U5MR) of 1.82 (95%CI: 1.21, 2.41). In Beboro, the CMR was 0.66 (95% CI: 0.48–0.84) and U5MR was 0.84 (95% CI: 0.43–1.25). The under-five male-to-female death ratio was 1.05:1 in Dembo and 4.5:1 in Beboro. Leading reported causes of death were malaria, neonatal complications, chronic disease, and respiratory infections.

DISCUSSION

Dembo’s high mortality rates reflected a population in acute distress with CMR and U5MR more than triple the regional average. In Beboro, marked sex disparities in reporting point to underestimation of the true mortality burden. Elevated mortality in the zones is likely driven by high malaria incidence and poor healthcare access. Following the survey, MSF made a number of adjustments to improve life-saving services. Results underscore the value of mortality estimation as an indicator of population health and a tool to evaluate whether humanitarian programs are meeting population needs.