Under‐Five Mortality in Humanitarian Emergencies: A Comparison of Face‐to‐Face and Mobile Phone Survey Estimates From Burkina Faso

OBJECTIVES: We evaluate the utility of mobile phone surveys (MPS) for estimating child mortality in Burkina Faso, where armed conflict and forced displacements hamper traditional face-to-face data collection on an important share of the territory. METHODS: We estimated under-five mortality from truncated birth histories collected in an MPS from September 2021 to October 2022. The sample consisted of telephone numbers collected in a prior face-to-face survey and an additional set of numbers generated through random digit dialling (RDD). We compared regionally disaggregated mortality estimates from the MPS with those from the 2021 Demographic and Health Survey (DHS), which could not cover parts of the national territory due to insecurity. RESULTS: Of 52,650 attempted phone numbers, 11,387 women of reproductive age were interviewed. Of these, 8077 were reached through RDD (36% lived in conflict-affected areas at the time of data collection) and 3310 via previously collected numbers (42% lived in conflict-affected areas). In regions not directly affected by conflict, under-five mortality rates have remained relatively stable over time: from 45 deaths per 1000 live births in 2018-2019 (95% CI: 36-54) to 58 in 2020-2022 (95% CI: 46-69). This finding mirrors the trend observed in the DHS data. In regions affected by armed conflict, however, the MPS data indicate a substantial increase in under-five mortality: From 47 deaths per 1000 live births in 2018-2019 (95% CI: 38-57) to 82 in 2020-2022 (95% CI: 67-98). This mortality reversal in conflict-affected areas is not apparent in the DHS, most likely due to the exclusion of the most insecure survey clusters from its sampling frame. CONCLUSION: MPS offers a viable alternative or complement to traditional face-to-face surveys for estimating child mortality in populations where insecurity limits face-to-face survey data collection.