PASS 2021 Update

Use the button(s) below to download the PASS 2021 installation file. If PASS 2021 is not yet installed on your computer, this will install the full version. If you already have PASS 2021 installed, this will update your current installation to the newest version. Your personal files will not be affected.

PASS 2021 Download

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File: PASS2021Setup_v21_0_5.exe
Size: 246.83 MB
Current Version: 21.0.5
Released: February 15, 2022

Click here for minimum System Requirements

Update Release Notes

This page lists the changes that have been made to PASS 2021 since it was released.

Version: 21.0.5

Released: February 15, 2022

1. Modified the allowable ranges for Cluster Size parameters M and m in the three Stepped-Wedge Cluster-Randomized Design procedures. The restriction that both parameters be ≥ 2 was found to be unnecessary. Now both parameters have allowed range of > 0.

2. An error in the “Mann-Whitney or Wilcoxon Rank-Sum Tests (Simulation)” and the “Tests for Two Means (Simulation)” routines has been corrected. The error caused the mean differences to be reported incorrectly in cases where the distribution’s first parameter was not the mean. The power calculations were correct.

Version: 21.0.4

Released: January 20, 2022

1. Corrected an error that caused the text in some single-value dropdown inputs on the Procedure Window not to be read correctly after selecting an item from the dropdown list.

2. Corrected an error in the Non-Inferiority (and Equivalence) Tests for the Difference (and Ratio) of Two Correlated Proportions procedures. When one of the cell proportions was zero, the software would incorrectly indicate an undefined table in some cases.

3. Corrected an issue with graphics dropdown buttons when using Windows 11. Dropdown buttons on plot format windows would display two images (one slightly offset from the other).

4. With this update, PASS 2021 is considered to be fully compatible with Windows 11.

5. Corrected the documentation for the Bland-Altman Method for Assessing Agreement in Method Comparison Studies procedure. NCT() was incorrectly stated as the inverse of Student’s non-central t distribution. This has been fixed such that NCT() is correctly stated as the cumulative distribution function of Student’s non-central t distribution.

Version: 21.0.3

Released: August 30, 2021

1. Corrected an error in displaying the Detail Numeric Reports in the Non-Inferiority Logrank Tests procedure.

2. Corrected an error in all GEE Tests procedures. The correlation matrix was not computed correctly when using Damped Exponential as the Pattern of ρ’s Across Time.

3. Corrected an error that occurred when parsing user-entered TO BY lists (e.g., "-2 to 2 by 0.1"). In some cases, rounding errors were causing unexpected results.

4. Corrected an error in the Superiority by a Margin Tests for Two Means in a Cluster-Randomized Design procedure when solving for M1. The search now converges.

5. Corrected an error in the Tests for Two Proportions in a Stepped-Wedge Cluster-Randomized Design procedure when solving for Effect Size with Effect Size Input Type set to Differences, Ratios, or Odds Ratios. The search now gives the correct result.

6. Corrected an error in the Tests for Two Means in a Stepped-Wedge Cluster-Randomized Design procedure when solving for Effect Size with Effect Size Input Type set to Differences. The search now gives the correct result.

7. Corrected an error in the Tests for Two Poisson Rates in a Stepped-Wedge Cluster-Randomized Design procedure when solving for Effect Size with Effect Size Input Type set to Differences or Rate Ratios. The search now gives the correct result.

8. Fixed the Dropout-Inflated Sample Size report in the Equivalence Tests for the Mean Ratio in a Three-Arm Trial (Normal Data) (Simulation) procedure. Results are now shown for all 3 groups.

9. Fixed the group allocation in the Equivalence Tests for the Mean Ratio in a Three-Arm Trial (Normal Data) (Simulation) procedure when solving for Sample Size. The allocation for nᴘ is now applied correctly when using unequal group allocation.

Version: 21.0.2

Released: February 19, 2021

1. Minor documentation updates.

2. Corrected an error in the Logrank Tests procedure. When using Mortality input, power and sample size were not computed correctly when entering M1 (Mortality - Control) and MR (Mortality Ratio = M2/M1). Power and sample size were correct when entering M1 (Mortality - Control) and M2 (Mortality - Treatment).

3. Corrected “Unhandled exception…” errors that occurred when opening PASS procedures in Windows 10 when the Microsoft Region language option Beta: Use Unicode UTF-8 for worldwide language support is active. (To determine if the option is active on your computer, see the steps below.)

Having the Beta: Use Unicode UTF-8 for worldwide language support option active may lead to other errors. We recommend that the option be disabled when using PASS.

To disable this option in Windows 10, perform the following steps with administrator rights on your computer:

a. Close all open documents and programs on your computer.
b. Press the Windows key.
c. Type “Settings.”
d. Select Time & Language.
e. Click Language.
f. Under Related settings, click Administrative language settings.
g. On the Region window, click the Administrative tab.
h. Click Change system locale. (Here you will need administrator rights.)
i. Clear the Beta: Use Unicode UTF-8 for worldwide language support checkbox.
j. Click OK.
k. Restart your computer.

Version: 21.0.1

Released: January 29, 2021

1. Initial Release of PASS 2021.

"I have been using NCSS for almost 20 years. I absolutely love it. It does everything [I need that] SPSS or SAS does, is more reasonably priced and user friendly and has wonderful customer support. If you have a problem, when you call a real person (who created the software) gently talks you through it. It is a great product and a great company."

Cheryl L. Meyer, PhD, Wright State University

I have been using NCSS in my high school class room for 22 years. I find it very easy to use and my students use it to calculate their results for their lab reports, science fair projects, and now they are using it for AP Research projects. It can be used for everything from the basics to the most advanced statistics. NCSS is very affordable for any high school budget.

David Buncher, High School Teacher, Miami, FL