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Sample size for Paired samples t-test

Input
Type I error - Alpha:
Type II error - Beta:

Mean difference:
Standard deviation of differences:
Result
Minimal required number of pairs:

For details, see the MedCalc manual: Sample size: Paired samples t-test.

MedCalc Software Ltd. Sample size for Paired samples t-test. https://www.medcalc.org/calc/sample-size-paired-samples-t-test.php (Version 23.2.1; accessed March 25, 2025)