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PASS is the industry-standard software for sample size calculation in clinical trials and biomedical research.

A serial number is required during installation. It can usually be found in a text file within the downloaded archive.

To ensure successful activation, it is recommended to disconnect from the internet during installation and the first launch.

After a successful installation, do not update the software. Any online update may cause the serial number to become invalid.

Includes over 1000 statistical test scenarios, covering various research designs from t-tests to survival analysis.

No programming required. Complete calculations by entering parameters in simple menus. Each tool includes detailed examples.

Generates plots of Power vs. Sample Size (N), helping researchers visually understand sample requirements under different parameters.

Estimating sample size before a study is a critical step for reliable results and is essential for grant proposals and protocol design.