Don't Spin the Pen: Two Alternative Methods for Second-Stage Sampling in Urban Cluster Surveys.

Hdl Handle:
http://hdl.handle.net/10144/18899
Title:
Don't Spin the Pen: Two Alternative Methods for Second-Stage Sampling in Urban Cluster Surveys.
Authors:
Grais, R; Rose, A; Guthmann, J P P
Journal:
Emerging Themes in Epidemiology
Abstract:
In two-stage cluster surveys, the traditional method used in second-stage sampling (in which the first household in a cluster is selected) is time-consuming and may result in biased estimates of the indicator of interest. Firstly, a random direction from the center of the cluster is selected, usually by spinning a pen. The houses along that direction are then counted out to the boundary of the cluster, and one is then selected at random to be the first household surveyed. This process favors households towards the center of the cluster, but it could easily be improved. During a recent meningitis vaccination coverage survey in Maradi, Niger, we compared this method of first household selection to two alternatives in urban zones: 1) using a superimposed grid on the map of the cluster area and randomly selecting an intersection; and 2) drawing the perimeter of the cluster area using a Global Positioning System (GPS) and randomly selecting one point within the perimeter. Although we only compared a limited number of clusters using each method, we found the sampling grid method to be the fastest and easiest for field survey teams, although it does require a map of the area. Selecting a random GPS point was also found to be a good method, once adequate training can be provided. Spinning the pen and counting households to the boundary was the most complicated and time-consuming. The two methods tested here represent simpler, quicker and potentially more robust alternatives to spinning the pen for cluster surveys in urban areas. However, in rural areas, these alternatives would favor initial household selection from lower density (or even potentially empty) areas. Bearing in mind these limitations, as well as available resources and feasibility, investigators should choose the most appropriate method for their particular survey context.
Affiliation:
Epicentre, 8, rue Saint Sabin, 75011 Paris, France. rebecca.grais@epicentre.msf.org
Publisher:
Published by BioMed Central
Issue Date:
2007
URI:
http://hdl.handle.net/10144/18899
DOI:
10.1186/1742-7622-4-8
PubMed ID:
17543102
Language:
en
ISSN:
1742-7622
Appears in Collections:
Health Politics

Full metadata record

DC FieldValue Language
dc.contributor.authorGrais, R-
dc.contributor.authorRose, A-
dc.contributor.authorGuthmann, J P P-
dc.date.accessioned2008-02-21T15:06:27Z-
dc.date.available2008-02-21T15:06:27Z-
dc.date.issued2007-
dc.identifier.citationDon't Spin the Pen: Two Alternative Methods for Second-Stage Sampling in Urban Cluster Surveys. 2007, 4:8notEmerg Themes Epidemiolen
dc.identifier.issn1742-7622-
dc.identifier.pmid17543102-
dc.identifier.doi10.1186/1742-7622-4-8-
dc.identifier.urihttp://hdl.handle.net/10144/18899-
dc.description.abstractIn two-stage cluster surveys, the traditional method used in second-stage sampling (in which the first household in a cluster is selected) is time-consuming and may result in biased estimates of the indicator of interest. Firstly, a random direction from the center of the cluster is selected, usually by spinning a pen. The houses along that direction are then counted out to the boundary of the cluster, and one is then selected at random to be the first household surveyed. This process favors households towards the center of the cluster, but it could easily be improved. During a recent meningitis vaccination coverage survey in Maradi, Niger, we compared this method of first household selection to two alternatives in urban zones: 1) using a superimposed grid on the map of the cluster area and randomly selecting an intersection; and 2) drawing the perimeter of the cluster area using a Global Positioning System (GPS) and randomly selecting one point within the perimeter. Although we only compared a limited number of clusters using each method, we found the sampling grid method to be the fastest and easiest for field survey teams, although it does require a map of the area. Selecting a random GPS point was also found to be a good method, once adequate training can be provided. Spinning the pen and counting households to the boundary was the most complicated and time-consuming. The two methods tested here represent simpler, quicker and potentially more robust alternatives to spinning the pen for cluster surveys in urban areas. However, in rural areas, these alternatives would favor initial household selection from lower density (or even potentially empty) areas. Bearing in mind these limitations, as well as available resources and feasibility, investigators should choose the most appropriate method for their particular survey context.en
dc.language.isoenen
dc.publisherPublished by BioMed Central-
dc.rightsArchived on this site by Open Access permissionen
dc.titleDon't Spin the Pen: Two Alternative Methods for Second-Stage Sampling in Urban Cluster Surveys.en
dc.contributor.departmentEpicentre, 8, rue Saint Sabin, 75011 Paris, France. rebecca.grais@epicentre.msf.orgen
dc.identifier.journalEmerging Themes in Epidemiologyen

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