Methodological issues of retrospective surveys for measuring mortality of highly clustered diseases: case study of the 2014-16 Ebola outbreak in Bo District, Sierra Leone.

Autor:	Caleo G; Manson Unit, Médecins Sans Frontières (MSF), London, UK.; MRC International Statistics and Epidemiology Group, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK., Lokuge K; National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australia., Kardamanidis K; Public Health Department MSF, Amsterdam, The Netherlands., Greig J; Manson Unit, Médecins Sans Frontières (MSF), London, UK., Belava J; Public Health Department MSF, Amsterdam, The Netherlands.; Vancouver Coastal Health, Vancouver, BC, Canada., Kilbride E; Public Health Department MSF, Amsterdam, The Netherlands., Sayui Turay A; District Health Management Team, Ministry of Health and Sanitation, Bo, Sierra Leone., Saffa G; District Health Management Team, Ministry of Health and Sanitation, Bo, Sierra Leone., Kremer R; Public Health Department MSF, Amsterdam, The Netherlands., Grandesso F; Department of Epidemiology and Training, Epicentre, Paris, France., Danis K; Santé publique France, The French National Public Health Agency (SpFrance), Saint-Maurice, France., Sprecher A; Medical Department, Médecins sans Frontières, Brussels, Belgium., Luca Di Tanna G; The George Institute for Global Health, University of New South Wales, Sydney, Australia., Baker H; Manson Unit, Médecins Sans Frontières (MSF), London, UK., Weiss HA; MRC International Statistics and Epidemiology Group, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
Jazyk:	angličtina
Zdroj:	Global health action [Glob Health Action] 2024 Dec 31; Vol. 17 (1), pp. 2331291. Date of Electronic Publication: 2024 Apr 26.
DOI:	10.1080/16549716.2024.2331291
Abstrakt:	Background: There is a lack of empirical data on design effects (DEFF) for mortality rate for highly clustered data such as with Ebola virus disease (EVD), along with a lack of documentation of methodological limitations and operational utility of mortality estimated from cluster-sampled studies when the DEFF is high. Objectives: The objectives of this paper are to report EVD mortality rate and DEFF estimates, and discuss the methodological limitations of cluster surveys when data are highly clustered such as during an EVD outbreak. Methods: We analysed the outputs of two independent population-based surveys conducted at the end of the 2014-2016 EVD outbreak in Bo District, Sierra Leone, in urban and rural areas. In each area, 35 clusters of 14 households were selected with probability proportional to population size. We collected information on morbidity, mortality and changes in household composition during the recall period (May 2014 to April 2015). Rates were calculated for all-cause, all-age, under-5 and EVD-specific mortality, respectively, by areas and overall. Crude and adjusted mortality rates were estimated using Poisson regression, accounting for the surveys sample weights and the clustered design. Results: Overall 980 households and 6,522 individuals participated in both surveys. A total of 64 deaths were reported, of which 20 were attributed to EVD. The crude and EVD-specific mortality rates were 0.35/10,000 person-days (95%CI: 0.23-0.52) and 0.12/10,000 person-days (95%CI: 0.05-0.32), respectively. The DEFF for EVD mortality was 5.53, and for non-EVD mortality, it was 1.53. DEFF for EVD-specific mortality was 6.18 in the rural area and 0.58 in the urban area. DEFF for non-EVD-specific mortality was 1.87 in the rural area and 0.44 in the urban area. Conclusion: Our findings demonstrate a high degree of clustering; this contributed to imprecise mortality estimates, which have limited utility when assessing the impact of disease. We provide DEFF estimates that can inform future cluster surveys and discuss design improvements to mitigate the limitations of surveys for highly clustered data.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu