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Sample size for Comparison of means

Input
Type I error - Alpha:  
Type II error - Beta: 
Difference: 
Standard deviation group 1: 
Standard deviation group 2: 
Ratio of sample sizes in Group 1 / Group 2: 
Result
Number of cases required in group 1:
Number of cases required in group 2:
Total sample size (2 groups together):

For details, see the MedCalc manual: Sample size: Comparison of two means.

How to cite this page

  • MedCalc Software Ltd. Sample size for Comparison of means. https://www.medcalc.org/calc/sample-size-comparison-of-means.php (Version 23.2.1; accessed March 26, 2025)