A two-stage cluster sampling method using gridded population data, a GIS, and Google EarthTM imagery in a population-based mortality survey in Iraq

International Journal of Health Geographics

Tim K Takaro²  Julie Rajaratnam⁴  Wiliam M Weiss³  Abraham Flaxman⁴  Gilbert Burnham³  Amy Hagopian⁴  Al Shatari SAE⁵  Nathaniel Bell¹  LP Galway² 

[1] Department of Surgery, University of British Columbia, West Mall, Vancouver, BC, Canada;Faculty of Health Sciences, Simon Fraser University, Blusson Hall 8888 University Drive, Burnaby, B.C, Canada V5A 1 S6, USA;School of Public Health, Johns Hopkins University, Baltimore, MD, USA;School of Public Health, University of Washington, Seattle, WA, USA;Human Development and Training Center, Iraqi, Ministry of Health, Iraq

关键词: Google Earth^TM;    Geographic information system (GIS);    Iraq war;    Conflict;    Mortality;    Population-based survey;    Cluster sampling;   

Others  :  821915
DOI  :  10.1186/1476-072X-11-12

 received in 2012-01-19, accepted in 2012-03-25,  发布年份 2012

【 摘 要 】

Background

Mortality estimates can measure and monitor the impacts of conflict on a population, guide humanitarian efforts, and help to better understand the public health impacts of conflict. Vital statistics registration and surveillance systems are rarely functional in conflict settings, posing a challenge of estimating mortality using retrospective population-based surveys.

Results

We present a two-stage cluster sampling method for application in population-based mortality surveys. The sampling method utilizes gridded population data and a geographic information system (GIS) to select clusters in the first sampling stage and Google Earth ^TM imagery and sampling grids to select households in the second sampling stage. The sampling method is implemented in a household mortality study in Iraq in 2011. Factors affecting feasibility and methodological quality are described.

Conclusion

Sampling is a challenge in retrospective population-based mortality studies and alternatives that improve on the conventional approaches are needed. The sampling strategy presented here was designed to generate a representative sample of the Iraqi population while reducing the potential for bias and considering the context specific challenges of the study setting. This sampling strategy, or variations on it, are adaptable and should be considered and tested in other conflict settings.

【 授权许可】

   
2012 Galway et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

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