Single, Double and Multiple Sampling Plans: Hypergeometric Distribution

Abstract

Systematic and standardized approach for monitoring and evaluating disease control programs is needed. The conventional sample survey methods are expensive, time consuming and need a great deal of resources. Lot Quality Assurance Sampling (LQAS) technique, originally a quality control tool in an industry, which was tried successfully for monitoring and evaluating immunization programs, leprosy, tuberculosis, sleeping sickness etc., control programs. Literature review suggests that all, except three, studies employing LQAS survey methodology used single sampling plan and normal approximation method to compute sample size. Hence, there is a need to develop formulae to obtain nomograms on sample sizes as ready reckoner when the variable of interest follows Hypergeometric distribution. The methods for sample size calculation using LQAS methodology under single/double, multiple sampling plans are provided separately for Hypegeometric distribution with/ without considering the Power are developed. Pragmatic solutions for the sample size and the corresponding acceptable number ‘d’ are obtained for diff erent sampling plans such as single, double and multiple sampling plans