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Disaster Epidemiology Lessons From Bam Earthquake Dec 26, 2003 Iran Part 5 : The methodological lessons from Bam earthquake. Ali Ardalan MD, MPH, PhD student in Epidemiology. 1. Learning objectives :
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Disaster Epidemiology Lessons From Bam Earthquake Dec 26, 2003 Iran Part 5: The methodological lessons from Bam earthquake Ali Ardalan MD, MPH, PhD student in Epidemiology 1
Learning objectives: • To understand some applications and limitations of epidemiologic studies in earthquakes • To understand the application and methodology of Rapid Health Assessment in Bam. • To learn about the application of Geographic- based sampling method in Bam. • To learn about important points of ethical issues of research in disasters 2
Challenges and problems facing Epidemiologists following the disasters • Political environment • Changing social conditions and demographics • Difficulty in applying standard epidemiologic techniques in the context of great destruction • Lack of time for organizing epidemiologic investigation • Absence of well defined population counts • Lack of active collaboration between scientists from different disciplines 3
Rapid Health Assessment after • the earthquake • Objectives: • To identify, define and prioritize potential impacts in disaster situations • To help mobilize resources and direct them to where they are most needed. 4
Rapid Health Assessment • The principles of methodology: • Simple consensus-based qualitative assessment process • Not replace the quantitative studies, but fills a gap until such studies are appropriate. • Can be used from the time disaster happens till some month later, or for any major stage-change in an extended crisis. 5
Rapid Health Assessment • Source of information: • Direct observation of the field • Reviewing of the pre-disaster records • Reviewing of community profiles in the news and on the Internet, and diverse reports. • Interviewing with local and national authorities • Interviewing with affected people 6
Rapid Health Assessment in the Bam Earthquake As part of a joint mission of the World Health organization (WHO) with the Iranian Ministry of Health (MoH), a rapid assessment was conducted on the health status of the affected population and health activities in Bam on Dec 27, 2003. 7
Survey Methodology-Phase 1: Feasibility study Interviews with local disaster managers Direct observation of the field Assessment of population-based design requirements 8
Ethical issues of population-based research in disasters Verbal consent Confidentiality of individual information The most important point,Peoplemust be informed that the interviews are unrelated to providing information for personal service deliveries to deal with their needs. 12
Geographic-based sampling design in disasters • A very useful tool in Bam, because of lack of a sampling frame of residential tents. 13
Geographic-based sampling plan Geographic zone Section 1 Main street Section 3 Cross-road Section 2 Square Selected start point 14
Geographic-based sampling plan Main street Cross-road 500 m Square Selected start point Tent Movement direction Minor street, Alley 15
Geographic-based sampling plan Main street Cross-road 500 m Square Selected start point Tent Movement direction Minor street, Alley 16
Geographic-based sampling plan Cross-road Square as selected start point Main street Minor street, Alley 500 m Tent Movement direction 17
Limitation of cross-sectional studies in post-disaster period of Bam earthquake • Potentialselection bias in determining the risk factors of mortality and injuries and also their incidence estimations 18
Population movement After the earthquake Zones Earthquake-strickenarea 19
The main construction materials of earthquake-stricken population houses based on a cross-sectional study on 19th and 20th days of post-disaster period in Bam 20
A consequence of cross-sectional studiesin post-disaster period of Bam Death by cross-sectional study 18 % Selection bias - 45 % Total death: 40 % of population 21
Conclusion: Considering the limitations of cross-sectional and case-control studies, it seems a retrospective cohort approach, for instance, based on before-quake list of governmental employees, would be decreases the aforementioned problem. 22