©
2005
Last
Updated
20 Nov 2005

FOR PDF FILE, CLICK ON YELLOW SQUARE
METHODOLOGY
pp. 107110 
Harris DR, Lemeshow S. Evaluation of the EPI survey
methodology for estimating relative risk. World Health Stat Q 44(3),
10714, 1991. 
pp. 111114 
Precision in estimation of relative risks using a
standardized sampling method proposed by the WHO Global Programme on AIDS was
evaluated using a Monte Carlo model simulating actual populations; the proposed
survey design represents a modification of the methodology used by the WHO
Expanded Programme on Immunization (EPI) to estimate immunization coverage among
children. This study suggests that in actual populations the proposed survey
strategy is a reasonable alternative to the use of simple random sampling (SRS)
at the second stage of cluster sampling. Although varying such population
characteristics as the seroprevalence rate, nonresponse rate, and rate of
misclassification of exposure failed to demonstrate a clear advantage of one
method over the other, the added cost and difficulty of implementing SRS under
field conditions warrant further consideration of the EPIlike methodology for
use in estimating relative risks.
PIP: Logistical and managerial constraints have prompted
classical probabilityproportionaltosize (PPS) cluster sampling to be modified
for application to surveys of immunization coverage. This World Health
Organization Expanded Program on Immunization (EPI) methodology aims to estimate
population rates accurate to within 10% of the true level. Concerned with the
accuracy and reliability of the methodology, researchers have employed a Monte
Carlo computer simulation model to evaluate the approach's precision in
estimating relative risks. Mimicking characteristics of typical African
populations, the Monte Carlo model suggests the proposed survey strategy to be a
viable alternative to simple random sampling (SRS) at the 2nd stage of cluster
sampling. Varying seroprevalence rate, nonresponse rate, and rate of
misclassification of exposure failed to prove 1 method advantageous over the
other. Given the cost and difficulty of classical sampling techniques,
researchers should consider the advantages of using the EPI methodology.
Return to RAPID SURVEYS (HOME)
Return
to RAPID SURVEYS REFERENCES  BY AUTHOR
Return to RAPID SURVEYS REFERENCES  BY YEAR
Return
to RAPID SURVEYS REFERENCES  BY TOPIC 