Prevalence Formula For Sample Size. X Z α22 p 1-p MOE 2 and Z α2 is the critical value of the Normal distribution at α2 eg. Highest value lowest value Midrange 2 x x n x N wx x w f x x f.
X Z α22 p 1-p MOE 2 and Z α2 is the critical value of the Normal distribution at α2 eg. If 5 d 005. Therefore the sample size can be calculated using the formula as 10000 196 2 05 1-05 005 2 10000 1 196 2 05 1-05 005 2 Therefore 370 customers.
Assumption of the table.
A sample of size n16448 will ensure that a 95 confidence interval estimate of the prevalence of breast cancer is within 010 or to within 10 women per 10000 of its true value. 2 2 1 d Z P n where n sample size Z Z statistic for a level of confidence P expected prevalence or proportion in proportion of one. An alternative approach of calculating the sample size is effect size. Sample Size Calculation Based on Effect Size.
