Inputs


This utility calcuates the sample size required to provide a desired probability of
detecting disease (
herdsensitivity) at the specified design prevalence, for a finite
population, assuming a test of
known sensitivity and 100%
specificity. These analyses
use an approximation of the hypergeometric distribution (MacDiarmid, SC (1988).
NZ Vet J, 36:3942).
Inputs are the size of the population, test sensitivity, the desired herdsensitivity
and the design (target) prevalence.
Outputs are:
 the number of samples required to be tested to provide the desired herdsensitivity
for the given design prevalence;
 a table and graph of sample sizes required to
provide the desired herdsensitivity, for the specified test sensitivity and
a range of population sizes and design prevalences.
