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Efficient Sample Size Calculator

Deployed

The Efficient Sample Size Calculator simulates the sample size needed to declare a population free-from-disease while explicitly accounting for the natural clustering behavior of hosts. The Calculator can be used to plan investigations using simple random sampling, high-harvest, or two-stage cluster sampling designs.

Geographical Scale

  • Population size of interest, regardless of the spatial scale

User Inputs

  • Population of interest
  • Average cluster size of hosts
  • Whether clusters are fixed or variable in size
  • Correlation in disease status among hosts sharing a cluster
  • Sensitivity of the diagnostic test used to declare CWD-positive

Outputs

  • The number of hosts that need to be tested without finding a positive case to have high probability (95%) that disease prevalence in the overall population is at or below 1% or 2%.

graph of sample size vs probability of freedom from disease at a given prevalence

Example output from the Efficient Sample Size Calculator.

More Information

For more information, go to the CWD Data Warehouse User Manual: Efficient Sample Size Calculator.

Code

To view the code, go to the GitHub Repository: Efficient Sample Size Calculator.

Citations