Confidence Interval Determination


Introduction: Confidence interval (C.I.) is a range providing an interval estimate to true but unknown population parameter. The confidence level (1-α) is the proportion of confidence intervals that cover the true parameter, i.e. a 95% C.I. is the interval that you are 95% certain contains the unknown population true value. Its relation with hypothesis test is that the 100(1-α)% confidence interval of the test statistic is the acceptance region of a 2-sided hypothesis test. If the test statistic is more extreme than the upper or lower bound of the confidence interval, the null hypothesis is rejected. The significance level of the test is the complement of the confidence level.



This program helps users to find confidence interval for various statistical and epidemiological studies, including proportion, correlation, rate, relative risk, odd ratios and diagnostic statistics. Besides this, McNemar’s Test for paired groups is also provided.






Survival Analysis

Phase II Clinical Trials

Epidemiological Studies

Confidence Intervals


1. One sample proportion

2. Two sample proportions

3. Correlation

4. Single incidence rate

5. Relative Risk and Attributable Risk

6. Odds Ratios, ARR, RRR, NNT, PEER

7. Diagnostic Statistics

8. McNemar’s Test