The validity and feasibility of a new method to estimate mortality in crisis-affected and resource-poor settings

Abstract Background Data for mortality rates are crucial to guide health interventions in crisis-affected and resource-poor settings. The methods currently available to collect mortality data in such settings feature important methodological limitations. We developed and validated a new method (the informant method) to provide near real-time mortality estimates in such settings. The objective was to assess the validity and feasibility of the informant method. Methods We selected four study sites: Kabul, Afghanistan; Mae La refugee camp, Thailand; Chiradzulu District, Malawi; and Lugufu and Mtabila refugee camps, Tanzania. We recorded information about all deaths in a 60-day period by asking key community informants and decedents’ next of kin to refer interviewers to bereaved households. We used the total number of deaths and population estimates to calculate mortality rates for 60-day and 30-day periods. For validation, we compared these rates with a best estimate of mortality using capture-recapture analysis with two further independent lists of deaths. For feasibility, time and cost inputs for the informant method were compared with those estimated for a retrospective mortality survey. We also assessed the feasibility of using verbal autopsy methods with the informant method (for Chiradzulu District only). Findings The population covered by the informant method was 76 476 people in Kabul, 43 794 in Mae La camp, 54 418 in Chiradzulu District, and 80 136 in Tanzania camps. The informant method showed moderate sensitivity (55·0% in Kabul, 64·0% in Mae La, 72·5% in Chiradzulu, and 67·7% in Tanzania), but performed better than the active surveillance system in the Tanzania refugee camps. The informant method required an average of 29% less time inputs and 33% less monetary inputs across all four study sites than retrospective surveys with a 6-month recall period. The addition of verbal autopsy was highly feasible, and enabled estimation of cause-attributable mortality. Interpretation The informant method currently features moderate sensitivity for accurately assessing mortality, but warrants further development, particularly considering its advantages over current options of better feasibility and near real-time estimates of mortality rates.