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Epi Hub

WHO/CDC standard tools for epidemiological analysis & surveillance

WHO Cluster Survey Calculator

30 x 7 EPI Cluster Survey Design - Standard WHO sample size calculation

Survey Parameters

SRS Sample

97

Cluster-Adjusted

146

Per Cluster

5

Total (adj. NR)

180

n = DEFF x z squared x p(1-p) / d squared = 1.5 x 1.96² x 0.5x0.50 / 0.1² = 146

Standard Designs Comparison

DesignClustersPer ClusterTotal
WHO 30x7 (Classic)307210
WHO 30x7 (Updated)307210
Your Design305150
Large Survey603180

Recommendations

Feasible sample size

Normal

Total of 180 households. Standard 30x7 design is practical for most field teams.