Estimate the proportion with a dichotomous result or finding in a single sample.

*This calculator gives both binomial and normal approximation to the proportion.*

**Instructions: **Enter parameters in the red cells. Answers will appear in blue below.

*1. Binomial "exact" calculation:*

**Proportion of positive results = P = x/N = **

**Lower bound = **

**Upper bound = **

*2. Normal approximation to the binomial calculation:*

Standard error of the mean = SEM = √x(N-x)/N^{3} =

α = (1-CL)/2 =

Standard normal deviate for α = Z_{α} =

**Proportion of positive results = P = x/N = **

**Lower bound = P - (Z _{α}*SEM) = **

**Upper bound = P + (Z _{α}*SEM) = **