Retrospective estimation of mortality in Somalia, 2014-2018: a statistical analysis

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By Abdihamid Warsame MSc, Séverine Frison PhD, Amy Gimma MSc, and Francesco Checchi PhD



Somalia regularly experiences drought-related crises, against the backdrop of a thirty-year old armed conflict. During 2010-2012, extreme food insecurity and famine were estimated to account for 256,000 deaths. Since 2014 Somalia has experienced recurrent below-average rainfall, with consecutive failed rains in late 2016 and 2017 leading to large-scale drought, displacement and epidemics. We wished to estimate mortality across Somalia from 2014 to 2018, and measure the excess death toll attributable to the 2017-2018 drought-triggered crisis.


We used a statistical approach akin to small-area estimation, and relying solely on existing data. We identified and reanalysed 91 household surveys done at the district level and estimating the crude (CDR) and under 5 years death rate (U5DR) over retrospective periods of 3-4 months. We captured datasets of candidate predictors of mortality with availability by district and month, as per a causal framework including climate, armed conflict intensity, forced displacement, food insecurity, nutritional status, disease burden, humanitarian and health service domains. We also reconstructed population denominators by district-month combining alternative census estimates and displacement data. We combined these data inputs into predictive models to estimate CDR and U5DR even where no ground data were available, and combined the predictions with population estimates to project death tolls. Excess mortality was estimated by constructing counterfactual no-crisis scenarios.


Between 2013 and 2018, Somalia’s population increased from 12.0 to 13.5 million, and internally displaced people or returnees reached 20% of the population. Using models comprising the incidence of armed conflict events, rate of nutritional therapy admissions, incidence of malaria and measles occurrence, we estimated that CDR ranged between 0.3 and 0.5 per 10,000 person-days during 2014-2018, but with an increase of about 15% during 2017-2018, translating to an excess death toll of 44,700 in the most likely counterfactual scenario, and as high as 163,800 in a pessimistic scenario. By contrast to 2010-2012, excess deaths were widespread across Somalia, including central and northern regions.


This analysis suggests that the 2017-2018 crisis had a lower, albeit still very substantial, mortality impact than its 2010-2012 predecessor. Despite modest elevations in death rate, crisis conditions were widespread and affected a population of millions. Potential study limitations we have identified include error in population estimates and under-reporting of child deaths, which we explore in sensitivity analyses. Humanitarian response to drought-related crises in Somalia needs to be strengthened, target the most vulnerable and emphasise very early interventions.