PASS 15 Update

Use the button(s) below to download the PASS 15 installation file. If PASS 15 is not yet installed on your computer, this will install the full version. If you already have PASS 15 installed, this will update your current installation to the newest version. Your personal files will not be affected.

PASS 15 Download

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File: PASS15Setup_v15_0_13.exe
Size: 122.98 MB
Current Version: 15.0.13
Released: February 10, 2020

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Update Release Notes

This page lists the changes that have been made to PASS 15 since it was released.

Version: 15.0.13

Released: February 10, 2020

1. Fixed errors in the Equivalence Tests for Two Means (Simulation) and Equivalence Tests for Paired Means (Simulation) procedures. When using symmetric equivalence limits and multiple values for M1, only the first scenario had symmetric limits.

2. Corrected a typo in the formula for Power using W5 on page 437-4 of the documentation of the Tests for the Ratio of Two Poisson Rates procedure. The formula incorrectly indicated that Power(W5) = 1 - φ(…). It has been corrected to Power(W5) = φ(…) so that it matches what is actually being calculated. This typo did not affect the calculated results of the procedure.

3. This is the final update to PASS 15.

Version: 15.0.12

Released: October 25, 2019

1. Corrected an error in the calculation of Power when solving for Sample Size in the Reliability Demonstration Tests of One Proportion with Adverse Events procedure. Type II Error (Beta) was being reported instead of Power. This has been corrected. Note that when solving for Alpha, the correct Power was reported.

Version: 15.0.11

Released: May 23, 2019

1. Fixed a “Subscript out of range” error in the Tests for Two Proportions in a Repeated Measures Design procedure that occurred when Group Allocation was set to “Enter total sample size and percentage in Group 1” and Definitions were being output in the report.

2. Corrected a summary statement error in the One-Sample Logrank Tests procedure. The wrong value was being reported for “proportion surviving in the historic control group” in the summary statement when Input Type = S0, HR. This error did not affect actual calculations nor results displayed in the Numeric Results table.

3. Corrected an error in the Equivalence Tests for the Ratio of Two Poisson Rates and Equivalence Tests for the Ratio of Two Negative Binomial Rates procedures. When 1/RL was entered for RU (or 1/RU was entered for RL), the output would always report RU as 1.25 (or RL as 0.8). The correct values for RU (or RL) were used in calculations so the reported sample sizes and power values were correct. Only the reported value for the upper or lower bound was incorrect. This has been fixed so that the reported values for RU (or RL) match the actual values used in calculations.

Version: 15.0.10

Released: November 2, 2018

1. Fixed power calculation error in the Tests for Two Correlated Proportions in a Matched Case-Control Design procedure. The author of the paper on which this procedure is based determined that the correction made in PASS 15 update 15.0.5 was unnecessary. The calculations in PASS have been updated to reflect the author’s corrections. This correction returns the PASS calculation results for the Tests for Two Correlated Proportions in a Matched Case-Control Design procedure to the same results obtained prior to PASS 15 update 15.0.5.

2. Fixed power calculation error in the Tests for Two Variances procedure. The power was not being calculated correctly in some cases when the group sample sizes are unequal.

3. Fixed documentation typos in the Non-Central Chi-Square Distribution in the Probability Calculator documentation.

Version: 15.0.9

Released: August 17, 2018

1. Corrected issues encountered in various procedures where the period is used in a way other than to represent a decimal symbol (e.g. in “D0.L”) when the computer language uses a comma as the decimal symbol. The period was incorrectly being replaced by a comma in non-numeric instances.

Version: 15.0.8

Released: July 6, 2018

1. Corrected a rare error in the Stepped-Wedge Design procedures. Fringe models with no real solution were reporting power of 1 when the power should have been returned as missing with no solution.

2. Corrected an error in the Multiple Contrasts (Simulation) procedure. When solving for Sample Size, the target power value was being set to 1-(User-Entered Value for Power). The correct input power value is now used.

3. Corrected an error that caused incorrect power and sample size calculations when entering “R1” in the Tests for Two Proportions in a Stratified Design (Cochran/Mantel-Haenszel Test) procedure when the computer’s system language setting was set to a South African language setting or any other language setting where R is a currency symbol.

4. Corrected a “Subscript out of Range” error in Hotelling’s One-Sample T2 procedure that occurred when the language setting on the machine uses a comma as the decimal.

Version: 15.0.7

Released: May 1, 2018

1. In several of the Cluster-Randomized Design procedures, the cluster size entry (M) offered the option to have decimal input, but PASS converted the decimals to integers. A correction was made so that those procedures properly use the decimal input for values of M. The option to specify the number of decimals for M in the reports was added to the Reports tab.

2. Fixed issue in the Tests for the Odds Ratio in Logistic Regression with One Binary X (Wald Test) procedure. When solving for Odds Ratio, the software would output strange values instead of missing values in cases where a solution is not possible.

3. Fixed issue in the Logrank Tests Accounting for Competing Risks procedure. The loss to follow-up adjustment wasn’t being applied correctly when searching for Hazard Ratio.

4. Minor corrections to the Lin's Concordance Correlation Coefficient documentation.

Version: 15.0.6

Released: February 6, 2018

1. Corrected summary statement errors in the Logrank Tests procedure output. The type of input was mislabeled in some cases.

2. Corrected some dropdown box options on the Repeated Measures Analysis procedure window. Not all of the available tests were listed for the test to base sample size calculations on and the test to include in summary statements. This was causing the program to output a statement for the wrong test in some cases.

3. Corrected mouseover message error in the Logrank Tests Accounting for Competing Risks procedure. The message for R (Accrual Time) indicated that 0 was a valid entry, but R must be greater than 0 in this procedure.

Version: 15.0.5

Released: November 3, 2017

1. Fixed power calculation error in Tests for Two Correlated Proportions in a Matched Case-Control Design. The author of the paper on which this procedure is based discovered a calculation error in his software used to create the results in the paper. The calculations in PASS and the validation results have been updated to reflect the author’s corrections.

2. Corrected error in Normality Tests procedure. In some cases the power was being drastically underestimated for the Skewness test.

3. Fixed rare Type Mismatch error in Group-Sequential Tests for Two Proportions (Simulation) and related procedures. An unused background setting was causing the error in rare situations.

Version: 15.0.4

Released: August 9, 2017

1. Fixed "Subscript out of Range" error in the Two-Sample T-Tests using Effect Size procedure that was occurring when the alternative hypothesis was one-sided.

Version: 15.0.3

Released: April 21, 2017

1. Improved the search function on the PASS Home window so that you can enter a Procedure # or template extension (e.g. “330” or “t330” or “.t330”) into the search bar to find the corresponding procedure.

2. Fixed documentation typos in the test statistic formulas for the Non-Inferiority, Superiority by a Margin, and Equivalence Tests for Two Survival Curves Using Cox's Proportional Hazards Model procedures. This did not affect calculations.

Version: 15.0.2

Released: February 14, 2017

1. Fixed minor issues with titles in the output.

Version: 15.0.1

Released: January 10, 2017

1. Initial Release of PASS 15.

NCSS is an excellent tool for clinical and epidemiological research that is both user friendly and economical with excellent support. It removes the "fear of statistics" from clinical research and makes research accessible to all curious clinicians.

Ted Rosenberg, MD MSc. FRCP(C), Clinical Assistant Professor, University of British Columbia

"PASS is a great program. It does so much and is easy to use. It’s much better than the other sample size programs I’ve used—it has helped me greatly in my research."

Ken Lawson, Ph.D., The University of Texas