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Sample size for Confidence interval of a difference between proportions

Confidence interval
Confidence Interval (%):
Input
Proportion in group 1 (%):
Proportion in group 2 (%):
Confidence interval width (2-sided):
Ratio of sample sizes in Group 1 / Group 2:
Results
Number of cases required in group 1:
Number of cases required in group 2:
Total sample size (2 groups together):

MedCalc Software Ltd. Sample size for Confidence interval of a difference between proportions. https://www.medcalc.org/calc/sample-size-ci-difference-between-proportions.php (Version 23.2.1; accessed March 25, 2025)